xref: /openbmc/linux/kernel/sysctl.c (revision 01a6e126)
1 /*
2  * sysctl.c: General linux system control interface
3  *
4  * Begun 24 March 1995, Stephen Tweedie
5  * Added /proc support, Dec 1995
6  * Added bdflush entry and intvec min/max checking, 2/23/96, Tom Dyas.
7  * Added hooks for /proc/sys/net (minor, minor patch), 96/4/1, Mike Shaver.
8  * Added kernel/java-{interpreter,appletviewer}, 96/5/10, Mike Shaver.
9  * Dynamic registration fixes, Stephen Tweedie.
10  * Added kswapd-interval, ctrl-alt-del, printk stuff, 1/8/97, Chris Horn.
11  * Made sysctl support optional via CONFIG_SYSCTL, 1/10/97, Chris
12  *  Horn.
13  * Added proc_doulongvec_ms_jiffies_minmax, 09/08/99, Carlos H. Bauer.
14  * Added proc_doulongvec_minmax, 09/08/99, Carlos H. Bauer.
15  * Changed linked lists to use list.h instead of lists.h, 02/24/00, Bill
16  *  Wendling.
17  * The list_for_each() macro wasn't appropriate for the sysctl loop.
18  *  Removed it and replaced it with older style, 03/23/00, Bill Wendling
19  */
20 
21 #include <linux/module.h>
22 #include <linux/aio.h>
23 #include <linux/mm.h>
24 #include <linux/swap.h>
25 #include <linux/slab.h>
26 #include <linux/sysctl.h>
27 #include <linux/bitmap.h>
28 #include <linux/signal.h>
29 #include <linux/printk.h>
30 #include <linux/proc_fs.h>
31 #include <linux/security.h>
32 #include <linux/ctype.h>
33 #include <linux/kmemleak.h>
34 #include <linux/fs.h>
35 #include <linux/init.h>
36 #include <linux/kernel.h>
37 #include <linux/kobject.h>
38 #include <linux/net.h>
39 #include <linux/sysrq.h>
40 #include <linux/highuid.h>
41 #include <linux/writeback.h>
42 #include <linux/ratelimit.h>
43 #include <linux/compaction.h>
44 #include <linux/hugetlb.h>
45 #include <linux/initrd.h>
46 #include <linux/key.h>
47 #include <linux/times.h>
48 #include <linux/limits.h>
49 #include <linux/dcache.h>
50 #include <linux/dnotify.h>
51 #include <linux/syscalls.h>
52 #include <linux/vmstat.h>
53 #include <linux/nfs_fs.h>
54 #include <linux/acpi.h>
55 #include <linux/reboot.h>
56 #include <linux/ftrace.h>
57 #include <linux/perf_event.h>
58 #include <linux/kprobes.h>
59 #include <linux/pipe_fs_i.h>
60 #include <linux/oom.h>
61 #include <linux/kmod.h>
62 #include <linux/capability.h>
63 #include <linux/binfmts.h>
64 #include <linux/sched/sysctl.h>
65 #include <linux/sched/coredump.h>
66 #include <linux/kexec.h>
67 #include <linux/bpf.h>
68 #include <linux/mount.h>
69 #include <linux/pipe_fs_i.h>
70 
71 #include <linux/uaccess.h>
72 #include <asm/processor.h>
73 
74 #ifdef CONFIG_X86
75 #include <asm/nmi.h>
76 #include <asm/stacktrace.h>
77 #include <asm/io.h>
78 #endif
79 #ifdef CONFIG_SPARC
80 #include <asm/setup.h>
81 #endif
82 #ifdef CONFIG_BSD_PROCESS_ACCT
83 #include <linux/acct.h>
84 #endif
85 #ifdef CONFIG_RT_MUTEXES
86 #include <linux/rtmutex.h>
87 #endif
88 #if defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_LOCK_STAT)
89 #include <linux/lockdep.h>
90 #endif
91 #ifdef CONFIG_CHR_DEV_SG
92 #include <scsi/sg.h>
93 #endif
94 
95 #ifdef CONFIG_LOCKUP_DETECTOR
96 #include <linux/nmi.h>
97 #endif
98 
99 #if defined(CONFIG_SYSCTL)
100 
101 /* External variables not in a header file. */
102 extern int suid_dumpable;
103 #ifdef CONFIG_COREDUMP
104 extern int core_uses_pid;
105 extern char core_pattern[];
106 extern unsigned int core_pipe_limit;
107 #endif
108 extern int pid_max;
109 extern int pid_max_min, pid_max_max;
110 extern int percpu_pagelist_fraction;
111 extern int latencytop_enabled;
112 extern unsigned int sysctl_nr_open_min, sysctl_nr_open_max;
113 #ifndef CONFIG_MMU
114 extern int sysctl_nr_trim_pages;
115 #endif
116 
117 /* Constants used for minimum and  maximum */
118 #ifdef CONFIG_LOCKUP_DETECTOR
119 static int sixty = 60;
120 #endif
121 
122 static int __maybe_unused neg_one = -1;
123 
124 static int zero;
125 static int __maybe_unused one = 1;
126 static int __maybe_unused two = 2;
127 static int __maybe_unused four = 4;
128 static unsigned long one_ul = 1;
129 static int one_hundred = 100;
130 static int one_thousand = 1000;
131 #ifdef CONFIG_PRINTK
132 static int ten_thousand = 10000;
133 #endif
134 #ifdef CONFIG_PERF_EVENTS
135 static int six_hundred_forty_kb = 640 * 1024;
136 #endif
137 
138 /* this is needed for the proc_doulongvec_minmax of vm_dirty_bytes */
139 static unsigned long dirty_bytes_min = 2 * PAGE_SIZE;
140 
141 /* this is needed for the proc_dointvec_minmax for [fs_]overflow UID and GID */
142 static int maxolduid = 65535;
143 static int minolduid;
144 
145 static int ngroups_max = NGROUPS_MAX;
146 static const int cap_last_cap = CAP_LAST_CAP;
147 
148 /*this is needed for proc_doulongvec_minmax of sysctl_hung_task_timeout_secs */
149 #ifdef CONFIG_DETECT_HUNG_TASK
150 static unsigned long hung_task_timeout_max = (LONG_MAX/HZ);
151 #endif
152 
153 #ifdef CONFIG_INOTIFY_USER
154 #include <linux/inotify.h>
155 #endif
156 #ifdef CONFIG_SPARC
157 #endif
158 
159 #ifdef __hppa__
160 extern int pwrsw_enabled;
161 #endif
162 
163 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
164 extern int unaligned_enabled;
165 #endif
166 
167 #ifdef CONFIG_IA64
168 extern int unaligned_dump_stack;
169 #endif
170 
171 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
172 extern int no_unaligned_warning;
173 #endif
174 
175 #ifdef CONFIG_PROC_SYSCTL
176 
177 /**
178  * enum sysctl_writes_mode - supported sysctl write modes
179  *
180  * @SYSCTL_WRITES_LEGACY: each write syscall must fully contain the sysctl value
181  * 	to be written, and multiple writes on the same sysctl file descriptor
182  * 	will rewrite the sysctl value, regardless of file position. No warning
183  * 	is issued when the initial position is not 0.
184  * @SYSCTL_WRITES_WARN: same as above but warn when the initial file position is
185  * 	not 0.
186  * @SYSCTL_WRITES_STRICT: writes to numeric sysctl entries must always be at
187  * 	file position 0 and the value must be fully contained in the buffer
188  * 	sent to the write syscall. If dealing with strings respect the file
189  * 	position, but restrict this to the max length of the buffer, anything
190  * 	passed the max lenght will be ignored. Multiple writes will append
191  * 	to the buffer.
192  *
193  * These write modes control how current file position affects the behavior of
194  * updating sysctl values through the proc interface on each write.
195  */
196 enum sysctl_writes_mode {
197 	SYSCTL_WRITES_LEGACY		= -1,
198 	SYSCTL_WRITES_WARN		= 0,
199 	SYSCTL_WRITES_STRICT		= 1,
200 };
201 
202 static enum sysctl_writes_mode sysctl_writes_strict = SYSCTL_WRITES_STRICT;
203 
204 static int proc_do_cad_pid(struct ctl_table *table, int write,
205 		  void __user *buffer, size_t *lenp, loff_t *ppos);
206 static int proc_taint(struct ctl_table *table, int write,
207 			       void __user *buffer, size_t *lenp, loff_t *ppos);
208 #endif
209 
210 #ifdef CONFIG_PRINTK
211 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
212 				void __user *buffer, size_t *lenp, loff_t *ppos);
213 #endif
214 
215 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
216 		void __user *buffer, size_t *lenp, loff_t *ppos);
217 #ifdef CONFIG_COREDUMP
218 static int proc_dostring_coredump(struct ctl_table *table, int write,
219 		void __user *buffer, size_t *lenp, loff_t *ppos);
220 #endif
221 static int proc_dopipe_max_size(struct ctl_table *table, int write,
222 		void __user *buffer, size_t *lenp, loff_t *ppos);
223 
224 #ifdef CONFIG_MAGIC_SYSRQ
225 /* Note: sysrq code uses it's own private copy */
226 static int __sysrq_enabled = CONFIG_MAGIC_SYSRQ_DEFAULT_ENABLE;
227 
228 static int sysrq_sysctl_handler(struct ctl_table *table, int write,
229 				void __user *buffer, size_t *lenp,
230 				loff_t *ppos)
231 {
232 	int error;
233 
234 	error = proc_dointvec(table, write, buffer, lenp, ppos);
235 	if (error)
236 		return error;
237 
238 	if (write)
239 		sysrq_toggle_support(__sysrq_enabled);
240 
241 	return 0;
242 }
243 
244 #endif
245 
246 static struct ctl_table kern_table[];
247 static struct ctl_table vm_table[];
248 static struct ctl_table fs_table[];
249 static struct ctl_table debug_table[];
250 static struct ctl_table dev_table[];
251 extern struct ctl_table random_table[];
252 #ifdef CONFIG_EPOLL
253 extern struct ctl_table epoll_table[];
254 #endif
255 
256 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
257 int sysctl_legacy_va_layout;
258 #endif
259 
260 /* The default sysctl tables: */
261 
262 static struct ctl_table sysctl_base_table[] = {
263 	{
264 		.procname	= "kernel",
265 		.mode		= 0555,
266 		.child		= kern_table,
267 	},
268 	{
269 		.procname	= "vm",
270 		.mode		= 0555,
271 		.child		= vm_table,
272 	},
273 	{
274 		.procname	= "fs",
275 		.mode		= 0555,
276 		.child		= fs_table,
277 	},
278 	{
279 		.procname	= "debug",
280 		.mode		= 0555,
281 		.child		= debug_table,
282 	},
283 	{
284 		.procname	= "dev",
285 		.mode		= 0555,
286 		.child		= dev_table,
287 	},
288 	{ }
289 };
290 
291 #ifdef CONFIG_SCHED_DEBUG
292 static int min_sched_granularity_ns = 100000;		/* 100 usecs */
293 static int max_sched_granularity_ns = NSEC_PER_SEC;	/* 1 second */
294 static int min_wakeup_granularity_ns;			/* 0 usecs */
295 static int max_wakeup_granularity_ns = NSEC_PER_SEC;	/* 1 second */
296 #ifdef CONFIG_SMP
297 static int min_sched_tunable_scaling = SCHED_TUNABLESCALING_NONE;
298 static int max_sched_tunable_scaling = SCHED_TUNABLESCALING_END-1;
299 #endif /* CONFIG_SMP */
300 #endif /* CONFIG_SCHED_DEBUG */
301 
302 #ifdef CONFIG_COMPACTION
303 static int min_extfrag_threshold;
304 static int max_extfrag_threshold = 1000;
305 #endif
306 
307 static struct ctl_table kern_table[] = {
308 	{
309 		.procname	= "sched_child_runs_first",
310 		.data		= &sysctl_sched_child_runs_first,
311 		.maxlen		= sizeof(unsigned int),
312 		.mode		= 0644,
313 		.proc_handler	= proc_dointvec,
314 	},
315 #ifdef CONFIG_SCHED_DEBUG
316 	{
317 		.procname	= "sched_min_granularity_ns",
318 		.data		= &sysctl_sched_min_granularity,
319 		.maxlen		= sizeof(unsigned int),
320 		.mode		= 0644,
321 		.proc_handler	= sched_proc_update_handler,
322 		.extra1		= &min_sched_granularity_ns,
323 		.extra2		= &max_sched_granularity_ns,
324 	},
325 	{
326 		.procname	= "sched_latency_ns",
327 		.data		= &sysctl_sched_latency,
328 		.maxlen		= sizeof(unsigned int),
329 		.mode		= 0644,
330 		.proc_handler	= sched_proc_update_handler,
331 		.extra1		= &min_sched_granularity_ns,
332 		.extra2		= &max_sched_granularity_ns,
333 	},
334 	{
335 		.procname	= "sched_wakeup_granularity_ns",
336 		.data		= &sysctl_sched_wakeup_granularity,
337 		.maxlen		= sizeof(unsigned int),
338 		.mode		= 0644,
339 		.proc_handler	= sched_proc_update_handler,
340 		.extra1		= &min_wakeup_granularity_ns,
341 		.extra2		= &max_wakeup_granularity_ns,
342 	},
343 #ifdef CONFIG_SMP
344 	{
345 		.procname	= "sched_tunable_scaling",
346 		.data		= &sysctl_sched_tunable_scaling,
347 		.maxlen		= sizeof(enum sched_tunable_scaling),
348 		.mode		= 0644,
349 		.proc_handler	= sched_proc_update_handler,
350 		.extra1		= &min_sched_tunable_scaling,
351 		.extra2		= &max_sched_tunable_scaling,
352 	},
353 	{
354 		.procname	= "sched_migration_cost_ns",
355 		.data		= &sysctl_sched_migration_cost,
356 		.maxlen		= sizeof(unsigned int),
357 		.mode		= 0644,
358 		.proc_handler	= proc_dointvec,
359 	},
360 	{
361 		.procname	= "sched_nr_migrate",
362 		.data		= &sysctl_sched_nr_migrate,
363 		.maxlen		= sizeof(unsigned int),
364 		.mode		= 0644,
365 		.proc_handler	= proc_dointvec,
366 	},
367 	{
368 		.procname	= "sched_time_avg_ms",
369 		.data		= &sysctl_sched_time_avg,
370 		.maxlen		= sizeof(unsigned int),
371 		.mode		= 0644,
372 		.proc_handler	= proc_dointvec_minmax,
373 		.extra1		= &one,
374 	},
375 #ifdef CONFIG_SCHEDSTATS
376 	{
377 		.procname	= "sched_schedstats",
378 		.data		= NULL,
379 		.maxlen		= sizeof(unsigned int),
380 		.mode		= 0644,
381 		.proc_handler	= sysctl_schedstats,
382 		.extra1		= &zero,
383 		.extra2		= &one,
384 	},
385 #endif /* CONFIG_SCHEDSTATS */
386 #endif /* CONFIG_SMP */
387 #ifdef CONFIG_NUMA_BALANCING
388 	{
389 		.procname	= "numa_balancing_scan_delay_ms",
390 		.data		= &sysctl_numa_balancing_scan_delay,
391 		.maxlen		= sizeof(unsigned int),
392 		.mode		= 0644,
393 		.proc_handler	= proc_dointvec,
394 	},
395 	{
396 		.procname	= "numa_balancing_scan_period_min_ms",
397 		.data		= &sysctl_numa_balancing_scan_period_min,
398 		.maxlen		= sizeof(unsigned int),
399 		.mode		= 0644,
400 		.proc_handler	= proc_dointvec,
401 	},
402 	{
403 		.procname	= "numa_balancing_scan_period_max_ms",
404 		.data		= &sysctl_numa_balancing_scan_period_max,
405 		.maxlen		= sizeof(unsigned int),
406 		.mode		= 0644,
407 		.proc_handler	= proc_dointvec,
408 	},
409 	{
410 		.procname	= "numa_balancing_scan_size_mb",
411 		.data		= &sysctl_numa_balancing_scan_size,
412 		.maxlen		= sizeof(unsigned int),
413 		.mode		= 0644,
414 		.proc_handler	= proc_dointvec_minmax,
415 		.extra1		= &one,
416 	},
417 	{
418 		.procname	= "numa_balancing",
419 		.data		= NULL, /* filled in by handler */
420 		.maxlen		= sizeof(unsigned int),
421 		.mode		= 0644,
422 		.proc_handler	= sysctl_numa_balancing,
423 		.extra1		= &zero,
424 		.extra2		= &one,
425 	},
426 #endif /* CONFIG_NUMA_BALANCING */
427 #endif /* CONFIG_SCHED_DEBUG */
428 	{
429 		.procname	= "sched_rt_period_us",
430 		.data		= &sysctl_sched_rt_period,
431 		.maxlen		= sizeof(unsigned int),
432 		.mode		= 0644,
433 		.proc_handler	= sched_rt_handler,
434 	},
435 	{
436 		.procname	= "sched_rt_runtime_us",
437 		.data		= &sysctl_sched_rt_runtime,
438 		.maxlen		= sizeof(int),
439 		.mode		= 0644,
440 		.proc_handler	= sched_rt_handler,
441 	},
442 	{
443 		.procname	= "sched_rr_timeslice_ms",
444 		.data		= &sysctl_sched_rr_timeslice,
445 		.maxlen		= sizeof(int),
446 		.mode		= 0644,
447 		.proc_handler	= sched_rr_handler,
448 	},
449 #ifdef CONFIG_SCHED_AUTOGROUP
450 	{
451 		.procname	= "sched_autogroup_enabled",
452 		.data		= &sysctl_sched_autogroup_enabled,
453 		.maxlen		= sizeof(unsigned int),
454 		.mode		= 0644,
455 		.proc_handler	= proc_dointvec_minmax,
456 		.extra1		= &zero,
457 		.extra2		= &one,
458 	},
459 #endif
460 #ifdef CONFIG_CFS_BANDWIDTH
461 	{
462 		.procname	= "sched_cfs_bandwidth_slice_us",
463 		.data		= &sysctl_sched_cfs_bandwidth_slice,
464 		.maxlen		= sizeof(unsigned int),
465 		.mode		= 0644,
466 		.proc_handler	= proc_dointvec_minmax,
467 		.extra1		= &one,
468 	},
469 #endif
470 #ifdef CONFIG_PROVE_LOCKING
471 	{
472 		.procname	= "prove_locking",
473 		.data		= &prove_locking,
474 		.maxlen		= sizeof(int),
475 		.mode		= 0644,
476 		.proc_handler	= proc_dointvec,
477 	},
478 #endif
479 #ifdef CONFIG_LOCK_STAT
480 	{
481 		.procname	= "lock_stat",
482 		.data		= &lock_stat,
483 		.maxlen		= sizeof(int),
484 		.mode		= 0644,
485 		.proc_handler	= proc_dointvec,
486 	},
487 #endif
488 	{
489 		.procname	= "panic",
490 		.data		= &panic_timeout,
491 		.maxlen		= sizeof(int),
492 		.mode		= 0644,
493 		.proc_handler	= proc_dointvec,
494 	},
495 #ifdef CONFIG_COREDUMP
496 	{
497 		.procname	= "core_uses_pid",
498 		.data		= &core_uses_pid,
499 		.maxlen		= sizeof(int),
500 		.mode		= 0644,
501 		.proc_handler	= proc_dointvec,
502 	},
503 	{
504 		.procname	= "core_pattern",
505 		.data		= core_pattern,
506 		.maxlen		= CORENAME_MAX_SIZE,
507 		.mode		= 0644,
508 		.proc_handler	= proc_dostring_coredump,
509 	},
510 	{
511 		.procname	= "core_pipe_limit",
512 		.data		= &core_pipe_limit,
513 		.maxlen		= sizeof(unsigned int),
514 		.mode		= 0644,
515 		.proc_handler	= proc_dointvec,
516 	},
517 #endif
518 #ifdef CONFIG_PROC_SYSCTL
519 	{
520 		.procname	= "tainted",
521 		.maxlen 	= sizeof(long),
522 		.mode		= 0644,
523 		.proc_handler	= proc_taint,
524 	},
525 	{
526 		.procname	= "sysctl_writes_strict",
527 		.data		= &sysctl_writes_strict,
528 		.maxlen		= sizeof(int),
529 		.mode		= 0644,
530 		.proc_handler	= proc_dointvec_minmax,
531 		.extra1		= &neg_one,
532 		.extra2		= &one,
533 	},
534 #endif
535 #ifdef CONFIG_LATENCYTOP
536 	{
537 		.procname	= "latencytop",
538 		.data		= &latencytop_enabled,
539 		.maxlen		= sizeof(int),
540 		.mode		= 0644,
541 		.proc_handler	= sysctl_latencytop,
542 	},
543 #endif
544 #ifdef CONFIG_BLK_DEV_INITRD
545 	{
546 		.procname	= "real-root-dev",
547 		.data		= &real_root_dev,
548 		.maxlen		= sizeof(int),
549 		.mode		= 0644,
550 		.proc_handler	= proc_dointvec,
551 	},
552 #endif
553 	{
554 		.procname	= "print-fatal-signals",
555 		.data		= &print_fatal_signals,
556 		.maxlen		= sizeof(int),
557 		.mode		= 0644,
558 		.proc_handler	= proc_dointvec,
559 	},
560 #ifdef CONFIG_SPARC
561 	{
562 		.procname	= "reboot-cmd",
563 		.data		= reboot_command,
564 		.maxlen		= 256,
565 		.mode		= 0644,
566 		.proc_handler	= proc_dostring,
567 	},
568 	{
569 		.procname	= "stop-a",
570 		.data		= &stop_a_enabled,
571 		.maxlen		= sizeof (int),
572 		.mode		= 0644,
573 		.proc_handler	= proc_dointvec,
574 	},
575 	{
576 		.procname	= "scons-poweroff",
577 		.data		= &scons_pwroff,
578 		.maxlen		= sizeof (int),
579 		.mode		= 0644,
580 		.proc_handler	= proc_dointvec,
581 	},
582 #endif
583 #ifdef CONFIG_SPARC64
584 	{
585 		.procname	= "tsb-ratio",
586 		.data		= &sysctl_tsb_ratio,
587 		.maxlen		= sizeof (int),
588 		.mode		= 0644,
589 		.proc_handler	= proc_dointvec,
590 	},
591 #endif
592 #ifdef __hppa__
593 	{
594 		.procname	= "soft-power",
595 		.data		= &pwrsw_enabled,
596 		.maxlen		= sizeof (int),
597 	 	.mode		= 0644,
598 		.proc_handler	= proc_dointvec,
599 	},
600 #endif
601 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_ALLOW
602 	{
603 		.procname	= "unaligned-trap",
604 		.data		= &unaligned_enabled,
605 		.maxlen		= sizeof (int),
606 		.mode		= 0644,
607 		.proc_handler	= proc_dointvec,
608 	},
609 #endif
610 	{
611 		.procname	= "ctrl-alt-del",
612 		.data		= &C_A_D,
613 		.maxlen		= sizeof(int),
614 		.mode		= 0644,
615 		.proc_handler	= proc_dointvec,
616 	},
617 #ifdef CONFIG_FUNCTION_TRACER
618 	{
619 		.procname	= "ftrace_enabled",
620 		.data		= &ftrace_enabled,
621 		.maxlen		= sizeof(int),
622 		.mode		= 0644,
623 		.proc_handler	= ftrace_enable_sysctl,
624 	},
625 #endif
626 #ifdef CONFIG_STACK_TRACER
627 	{
628 		.procname	= "stack_tracer_enabled",
629 		.data		= &stack_tracer_enabled,
630 		.maxlen		= sizeof(int),
631 		.mode		= 0644,
632 		.proc_handler	= stack_trace_sysctl,
633 	},
634 #endif
635 #ifdef CONFIG_TRACING
636 	{
637 		.procname	= "ftrace_dump_on_oops",
638 		.data		= &ftrace_dump_on_oops,
639 		.maxlen		= sizeof(int),
640 		.mode		= 0644,
641 		.proc_handler	= proc_dointvec,
642 	},
643 	{
644 		.procname	= "traceoff_on_warning",
645 		.data		= &__disable_trace_on_warning,
646 		.maxlen		= sizeof(__disable_trace_on_warning),
647 		.mode		= 0644,
648 		.proc_handler	= proc_dointvec,
649 	},
650 	{
651 		.procname	= "tracepoint_printk",
652 		.data		= &tracepoint_printk,
653 		.maxlen		= sizeof(tracepoint_printk),
654 		.mode		= 0644,
655 		.proc_handler	= tracepoint_printk_sysctl,
656 	},
657 #endif
658 #ifdef CONFIG_KEXEC_CORE
659 	{
660 		.procname	= "kexec_load_disabled",
661 		.data		= &kexec_load_disabled,
662 		.maxlen		= sizeof(int),
663 		.mode		= 0644,
664 		/* only handle a transition from default "0" to "1" */
665 		.proc_handler	= proc_dointvec_minmax,
666 		.extra1		= &one,
667 		.extra2		= &one,
668 	},
669 #endif
670 #ifdef CONFIG_MODULES
671 	{
672 		.procname	= "modprobe",
673 		.data		= &modprobe_path,
674 		.maxlen		= KMOD_PATH_LEN,
675 		.mode		= 0644,
676 		.proc_handler	= proc_dostring,
677 	},
678 	{
679 		.procname	= "modules_disabled",
680 		.data		= &modules_disabled,
681 		.maxlen		= sizeof(int),
682 		.mode		= 0644,
683 		/* only handle a transition from default "0" to "1" */
684 		.proc_handler	= proc_dointvec_minmax,
685 		.extra1		= &one,
686 		.extra2		= &one,
687 	},
688 #endif
689 #ifdef CONFIG_UEVENT_HELPER
690 	{
691 		.procname	= "hotplug",
692 		.data		= &uevent_helper,
693 		.maxlen		= UEVENT_HELPER_PATH_LEN,
694 		.mode		= 0644,
695 		.proc_handler	= proc_dostring,
696 	},
697 #endif
698 #ifdef CONFIG_CHR_DEV_SG
699 	{
700 		.procname	= "sg-big-buff",
701 		.data		= &sg_big_buff,
702 		.maxlen		= sizeof (int),
703 		.mode		= 0444,
704 		.proc_handler	= proc_dointvec,
705 	},
706 #endif
707 #ifdef CONFIG_BSD_PROCESS_ACCT
708 	{
709 		.procname	= "acct",
710 		.data		= &acct_parm,
711 		.maxlen		= 3*sizeof(int),
712 		.mode		= 0644,
713 		.proc_handler	= proc_dointvec,
714 	},
715 #endif
716 #ifdef CONFIG_MAGIC_SYSRQ
717 	{
718 		.procname	= "sysrq",
719 		.data		= &__sysrq_enabled,
720 		.maxlen		= sizeof (int),
721 		.mode		= 0644,
722 		.proc_handler	= sysrq_sysctl_handler,
723 	},
724 #endif
725 #ifdef CONFIG_PROC_SYSCTL
726 	{
727 		.procname	= "cad_pid",
728 		.data		= NULL,
729 		.maxlen		= sizeof (int),
730 		.mode		= 0600,
731 		.proc_handler	= proc_do_cad_pid,
732 	},
733 #endif
734 	{
735 		.procname	= "threads-max",
736 		.data		= NULL,
737 		.maxlen		= sizeof(int),
738 		.mode		= 0644,
739 		.proc_handler	= sysctl_max_threads,
740 	},
741 	{
742 		.procname	= "random",
743 		.mode		= 0555,
744 		.child		= random_table,
745 	},
746 	{
747 		.procname	= "usermodehelper",
748 		.mode		= 0555,
749 		.child		= usermodehelper_table,
750 	},
751 	{
752 		.procname	= "overflowuid",
753 		.data		= &overflowuid,
754 		.maxlen		= sizeof(int),
755 		.mode		= 0644,
756 		.proc_handler	= proc_dointvec_minmax,
757 		.extra1		= &minolduid,
758 		.extra2		= &maxolduid,
759 	},
760 	{
761 		.procname	= "overflowgid",
762 		.data		= &overflowgid,
763 		.maxlen		= sizeof(int),
764 		.mode		= 0644,
765 		.proc_handler	= proc_dointvec_minmax,
766 		.extra1		= &minolduid,
767 		.extra2		= &maxolduid,
768 	},
769 #ifdef CONFIG_S390
770 #ifdef CONFIG_MATHEMU
771 	{
772 		.procname	= "ieee_emulation_warnings",
773 		.data		= &sysctl_ieee_emulation_warnings,
774 		.maxlen		= sizeof(int),
775 		.mode		= 0644,
776 		.proc_handler	= proc_dointvec,
777 	},
778 #endif
779 	{
780 		.procname	= "userprocess_debug",
781 		.data		= &show_unhandled_signals,
782 		.maxlen		= sizeof(int),
783 		.mode		= 0644,
784 		.proc_handler	= proc_dointvec,
785 	},
786 #endif
787 	{
788 		.procname	= "pid_max",
789 		.data		= &pid_max,
790 		.maxlen		= sizeof (int),
791 		.mode		= 0644,
792 		.proc_handler	= proc_dointvec_minmax,
793 		.extra1		= &pid_max_min,
794 		.extra2		= &pid_max_max,
795 	},
796 	{
797 		.procname	= "panic_on_oops",
798 		.data		= &panic_on_oops,
799 		.maxlen		= sizeof(int),
800 		.mode		= 0644,
801 		.proc_handler	= proc_dointvec,
802 	},
803 #if defined CONFIG_PRINTK
804 	{
805 		.procname	= "printk",
806 		.data		= &console_loglevel,
807 		.maxlen		= 4*sizeof(int),
808 		.mode		= 0644,
809 		.proc_handler	= proc_dointvec,
810 	},
811 	{
812 		.procname	= "printk_ratelimit",
813 		.data		= &printk_ratelimit_state.interval,
814 		.maxlen		= sizeof(int),
815 		.mode		= 0644,
816 		.proc_handler	= proc_dointvec_jiffies,
817 	},
818 	{
819 		.procname	= "printk_ratelimit_burst",
820 		.data		= &printk_ratelimit_state.burst,
821 		.maxlen		= sizeof(int),
822 		.mode		= 0644,
823 		.proc_handler	= proc_dointvec,
824 	},
825 	{
826 		.procname	= "printk_delay",
827 		.data		= &printk_delay_msec,
828 		.maxlen		= sizeof(int),
829 		.mode		= 0644,
830 		.proc_handler	= proc_dointvec_minmax,
831 		.extra1		= &zero,
832 		.extra2		= &ten_thousand,
833 	},
834 	{
835 		.procname	= "printk_devkmsg",
836 		.data		= devkmsg_log_str,
837 		.maxlen		= DEVKMSG_STR_MAX_SIZE,
838 		.mode		= 0644,
839 		.proc_handler	= devkmsg_sysctl_set_loglvl,
840 	},
841 	{
842 		.procname	= "dmesg_restrict",
843 		.data		= &dmesg_restrict,
844 		.maxlen		= sizeof(int),
845 		.mode		= 0644,
846 		.proc_handler	= proc_dointvec_minmax_sysadmin,
847 		.extra1		= &zero,
848 		.extra2		= &one,
849 	},
850 	{
851 		.procname	= "kptr_restrict",
852 		.data		= &kptr_restrict,
853 		.maxlen		= sizeof(int),
854 		.mode		= 0644,
855 		.proc_handler	= proc_dointvec_minmax_sysadmin,
856 		.extra1		= &zero,
857 		.extra2		= &two,
858 	},
859 #endif
860 	{
861 		.procname	= "ngroups_max",
862 		.data		= &ngroups_max,
863 		.maxlen		= sizeof (int),
864 		.mode		= 0444,
865 		.proc_handler	= proc_dointvec,
866 	},
867 	{
868 		.procname	= "cap_last_cap",
869 		.data		= (void *)&cap_last_cap,
870 		.maxlen		= sizeof(int),
871 		.mode		= 0444,
872 		.proc_handler	= proc_dointvec,
873 	},
874 #if defined(CONFIG_LOCKUP_DETECTOR)
875 	{
876 		.procname       = "watchdog",
877 		.data		= &watchdog_user_enabled,
878 		.maxlen		= sizeof(int),
879 		.mode		= 0644,
880 		.proc_handler   = proc_watchdog,
881 		.extra1		= &zero,
882 		.extra2		= &one,
883 	},
884 	{
885 		.procname	= "watchdog_thresh",
886 		.data		= &watchdog_thresh,
887 		.maxlen		= sizeof(int),
888 		.mode		= 0644,
889 		.proc_handler	= proc_watchdog_thresh,
890 		.extra1		= &zero,
891 		.extra2		= &sixty,
892 	},
893 	{
894 		.procname       = "nmi_watchdog",
895 		.data		= &nmi_watchdog_user_enabled,
896 		.maxlen		= sizeof(int),
897 		.mode		= NMI_WATCHDOG_SYSCTL_PERM,
898 		.proc_handler   = proc_nmi_watchdog,
899 		.extra1		= &zero,
900 		.extra2		= &one,
901 	},
902 	{
903 		.procname	= "watchdog_cpumask",
904 		.data		= &watchdog_cpumask_bits,
905 		.maxlen		= NR_CPUS,
906 		.mode		= 0644,
907 		.proc_handler	= proc_watchdog_cpumask,
908 	},
909 #ifdef CONFIG_SOFTLOCKUP_DETECTOR
910 	{
911 		.procname       = "soft_watchdog",
912 		.data		= &soft_watchdog_user_enabled,
913 		.maxlen		= sizeof(int),
914 		.mode		= 0644,
915 		.proc_handler   = proc_soft_watchdog,
916 		.extra1		= &zero,
917 		.extra2		= &one,
918 	},
919 	{
920 		.procname	= "softlockup_panic",
921 		.data		= &softlockup_panic,
922 		.maxlen		= sizeof(int),
923 		.mode		= 0644,
924 		.proc_handler	= proc_dointvec_minmax,
925 		.extra1		= &zero,
926 		.extra2		= &one,
927 	},
928 #ifdef CONFIG_SMP
929 	{
930 		.procname	= "softlockup_all_cpu_backtrace",
931 		.data		= &sysctl_softlockup_all_cpu_backtrace,
932 		.maxlen		= sizeof(int),
933 		.mode		= 0644,
934 		.proc_handler	= proc_dointvec_minmax,
935 		.extra1		= &zero,
936 		.extra2		= &one,
937 	},
938 #endif /* CONFIG_SMP */
939 #endif
940 #ifdef CONFIG_HARDLOCKUP_DETECTOR
941 	{
942 		.procname	= "hardlockup_panic",
943 		.data		= &hardlockup_panic,
944 		.maxlen		= sizeof(int),
945 		.mode		= 0644,
946 		.proc_handler	= proc_dointvec_minmax,
947 		.extra1		= &zero,
948 		.extra2		= &one,
949 	},
950 #ifdef CONFIG_SMP
951 	{
952 		.procname	= "hardlockup_all_cpu_backtrace",
953 		.data		= &sysctl_hardlockup_all_cpu_backtrace,
954 		.maxlen		= sizeof(int),
955 		.mode		= 0644,
956 		.proc_handler	= proc_dointvec_minmax,
957 		.extra1		= &zero,
958 		.extra2		= &one,
959 	},
960 #endif /* CONFIG_SMP */
961 #endif
962 #endif
963 
964 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86)
965 	{
966 		.procname       = "unknown_nmi_panic",
967 		.data           = &unknown_nmi_panic,
968 		.maxlen         = sizeof (int),
969 		.mode           = 0644,
970 		.proc_handler   = proc_dointvec,
971 	},
972 #endif
973 #if defined(CONFIG_X86)
974 	{
975 		.procname	= "panic_on_unrecovered_nmi",
976 		.data		= &panic_on_unrecovered_nmi,
977 		.maxlen		= sizeof(int),
978 		.mode		= 0644,
979 		.proc_handler	= proc_dointvec,
980 	},
981 	{
982 		.procname	= "panic_on_io_nmi",
983 		.data		= &panic_on_io_nmi,
984 		.maxlen		= sizeof(int),
985 		.mode		= 0644,
986 		.proc_handler	= proc_dointvec,
987 	},
988 #ifdef CONFIG_DEBUG_STACKOVERFLOW
989 	{
990 		.procname	= "panic_on_stackoverflow",
991 		.data		= &sysctl_panic_on_stackoverflow,
992 		.maxlen		= sizeof(int),
993 		.mode		= 0644,
994 		.proc_handler	= proc_dointvec,
995 	},
996 #endif
997 	{
998 		.procname	= "bootloader_type",
999 		.data		= &bootloader_type,
1000 		.maxlen		= sizeof (int),
1001 		.mode		= 0444,
1002 		.proc_handler	= proc_dointvec,
1003 	},
1004 	{
1005 		.procname	= "bootloader_version",
1006 		.data		= &bootloader_version,
1007 		.maxlen		= sizeof (int),
1008 		.mode		= 0444,
1009 		.proc_handler	= proc_dointvec,
1010 	},
1011 	{
1012 		.procname	= "io_delay_type",
1013 		.data		= &io_delay_type,
1014 		.maxlen		= sizeof(int),
1015 		.mode		= 0644,
1016 		.proc_handler	= proc_dointvec,
1017 	},
1018 #endif
1019 #if defined(CONFIG_MMU)
1020 	{
1021 		.procname	= "randomize_va_space",
1022 		.data		= &randomize_va_space,
1023 		.maxlen		= sizeof(int),
1024 		.mode		= 0644,
1025 		.proc_handler	= proc_dointvec,
1026 	},
1027 #endif
1028 #if defined(CONFIG_S390) && defined(CONFIG_SMP)
1029 	{
1030 		.procname	= "spin_retry",
1031 		.data		= &spin_retry,
1032 		.maxlen		= sizeof (int),
1033 		.mode		= 0644,
1034 		.proc_handler	= proc_dointvec,
1035 	},
1036 #endif
1037 #if	defined(CONFIG_ACPI_SLEEP) && defined(CONFIG_X86)
1038 	{
1039 		.procname	= "acpi_video_flags",
1040 		.data		= &acpi_realmode_flags,
1041 		.maxlen		= sizeof (unsigned long),
1042 		.mode		= 0644,
1043 		.proc_handler	= proc_doulongvec_minmax,
1044 	},
1045 #endif
1046 #ifdef CONFIG_SYSCTL_ARCH_UNALIGN_NO_WARN
1047 	{
1048 		.procname	= "ignore-unaligned-usertrap",
1049 		.data		= &no_unaligned_warning,
1050 		.maxlen		= sizeof (int),
1051 	 	.mode		= 0644,
1052 		.proc_handler	= proc_dointvec,
1053 	},
1054 #endif
1055 #ifdef CONFIG_IA64
1056 	{
1057 		.procname	= "unaligned-dump-stack",
1058 		.data		= &unaligned_dump_stack,
1059 		.maxlen		= sizeof (int),
1060 		.mode		= 0644,
1061 		.proc_handler	= proc_dointvec,
1062 	},
1063 #endif
1064 #ifdef CONFIG_DETECT_HUNG_TASK
1065 	{
1066 		.procname	= "hung_task_panic",
1067 		.data		= &sysctl_hung_task_panic,
1068 		.maxlen		= sizeof(int),
1069 		.mode		= 0644,
1070 		.proc_handler	= proc_dointvec_minmax,
1071 		.extra1		= &zero,
1072 		.extra2		= &one,
1073 	},
1074 	{
1075 		.procname	= "hung_task_check_count",
1076 		.data		= &sysctl_hung_task_check_count,
1077 		.maxlen		= sizeof(int),
1078 		.mode		= 0644,
1079 		.proc_handler	= proc_dointvec_minmax,
1080 		.extra1		= &zero,
1081 	},
1082 	{
1083 		.procname	= "hung_task_timeout_secs",
1084 		.data		= &sysctl_hung_task_timeout_secs,
1085 		.maxlen		= sizeof(unsigned long),
1086 		.mode		= 0644,
1087 		.proc_handler	= proc_dohung_task_timeout_secs,
1088 		.extra2		= &hung_task_timeout_max,
1089 	},
1090 	{
1091 		.procname	= "hung_task_warnings",
1092 		.data		= &sysctl_hung_task_warnings,
1093 		.maxlen		= sizeof(int),
1094 		.mode		= 0644,
1095 		.proc_handler	= proc_dointvec_minmax,
1096 		.extra1		= &neg_one,
1097 	},
1098 #endif
1099 #ifdef CONFIG_RT_MUTEXES
1100 	{
1101 		.procname	= "max_lock_depth",
1102 		.data		= &max_lock_depth,
1103 		.maxlen		= sizeof(int),
1104 		.mode		= 0644,
1105 		.proc_handler	= proc_dointvec,
1106 	},
1107 #endif
1108 	{
1109 		.procname	= "poweroff_cmd",
1110 		.data		= &poweroff_cmd,
1111 		.maxlen		= POWEROFF_CMD_PATH_LEN,
1112 		.mode		= 0644,
1113 		.proc_handler	= proc_dostring,
1114 	},
1115 #ifdef CONFIG_KEYS
1116 	{
1117 		.procname	= "keys",
1118 		.mode		= 0555,
1119 		.child		= key_sysctls,
1120 	},
1121 #endif
1122 #ifdef CONFIG_PERF_EVENTS
1123 	/*
1124 	 * User-space scripts rely on the existence of this file
1125 	 * as a feature check for perf_events being enabled.
1126 	 *
1127 	 * So it's an ABI, do not remove!
1128 	 */
1129 	{
1130 		.procname	= "perf_event_paranoid",
1131 		.data		= &sysctl_perf_event_paranoid,
1132 		.maxlen		= sizeof(sysctl_perf_event_paranoid),
1133 		.mode		= 0644,
1134 		.proc_handler	= proc_dointvec,
1135 	},
1136 	{
1137 		.procname	= "perf_event_mlock_kb",
1138 		.data		= &sysctl_perf_event_mlock,
1139 		.maxlen		= sizeof(sysctl_perf_event_mlock),
1140 		.mode		= 0644,
1141 		.proc_handler	= proc_dointvec,
1142 	},
1143 	{
1144 		.procname	= "perf_event_max_sample_rate",
1145 		.data		= &sysctl_perf_event_sample_rate,
1146 		.maxlen		= sizeof(sysctl_perf_event_sample_rate),
1147 		.mode		= 0644,
1148 		.proc_handler	= perf_proc_update_handler,
1149 		.extra1		= &one,
1150 	},
1151 	{
1152 		.procname	= "perf_cpu_time_max_percent",
1153 		.data		= &sysctl_perf_cpu_time_max_percent,
1154 		.maxlen		= sizeof(sysctl_perf_cpu_time_max_percent),
1155 		.mode		= 0644,
1156 		.proc_handler	= perf_cpu_time_max_percent_handler,
1157 		.extra1		= &zero,
1158 		.extra2		= &one_hundred,
1159 	},
1160 	{
1161 		.procname	= "perf_event_max_stack",
1162 		.data		= &sysctl_perf_event_max_stack,
1163 		.maxlen		= sizeof(sysctl_perf_event_max_stack),
1164 		.mode		= 0644,
1165 		.proc_handler	= perf_event_max_stack_handler,
1166 		.extra1		= &zero,
1167 		.extra2		= &six_hundred_forty_kb,
1168 	},
1169 	{
1170 		.procname	= "perf_event_max_contexts_per_stack",
1171 		.data		= &sysctl_perf_event_max_contexts_per_stack,
1172 		.maxlen		= sizeof(sysctl_perf_event_max_contexts_per_stack),
1173 		.mode		= 0644,
1174 		.proc_handler	= perf_event_max_stack_handler,
1175 		.extra1		= &zero,
1176 		.extra2		= &one_thousand,
1177 	},
1178 #endif
1179 	{
1180 		.procname	= "panic_on_warn",
1181 		.data		= &panic_on_warn,
1182 		.maxlen		= sizeof(int),
1183 		.mode		= 0644,
1184 		.proc_handler	= proc_dointvec_minmax,
1185 		.extra1		= &zero,
1186 		.extra2		= &one,
1187 	},
1188 #if defined(CONFIG_SMP) && defined(CONFIG_NO_HZ_COMMON)
1189 	{
1190 		.procname	= "timer_migration",
1191 		.data		= &sysctl_timer_migration,
1192 		.maxlen		= sizeof(unsigned int),
1193 		.mode		= 0644,
1194 		.proc_handler	= timer_migration_handler,
1195 		.extra1		= &zero,
1196 		.extra2		= &one,
1197 	},
1198 #endif
1199 #ifdef CONFIG_BPF_SYSCALL
1200 	{
1201 		.procname	= "unprivileged_bpf_disabled",
1202 		.data		= &sysctl_unprivileged_bpf_disabled,
1203 		.maxlen		= sizeof(sysctl_unprivileged_bpf_disabled),
1204 		.mode		= 0644,
1205 		/* only handle a transition from default "0" to "1" */
1206 		.proc_handler	= proc_dointvec_minmax,
1207 		.extra1		= &one,
1208 		.extra2		= &one,
1209 	},
1210 #endif
1211 #if defined(CONFIG_TREE_RCU) || defined(CONFIG_PREEMPT_RCU)
1212 	{
1213 		.procname	= "panic_on_rcu_stall",
1214 		.data		= &sysctl_panic_on_rcu_stall,
1215 		.maxlen		= sizeof(sysctl_panic_on_rcu_stall),
1216 		.mode		= 0644,
1217 		.proc_handler	= proc_dointvec_minmax,
1218 		.extra1		= &zero,
1219 		.extra2		= &one,
1220 	},
1221 #endif
1222 	{ }
1223 };
1224 
1225 static struct ctl_table vm_table[] = {
1226 	{
1227 		.procname	= "overcommit_memory",
1228 		.data		= &sysctl_overcommit_memory,
1229 		.maxlen		= sizeof(sysctl_overcommit_memory),
1230 		.mode		= 0644,
1231 		.proc_handler	= proc_dointvec_minmax,
1232 		.extra1		= &zero,
1233 		.extra2		= &two,
1234 	},
1235 	{
1236 		.procname	= "panic_on_oom",
1237 		.data		= &sysctl_panic_on_oom,
1238 		.maxlen		= sizeof(sysctl_panic_on_oom),
1239 		.mode		= 0644,
1240 		.proc_handler	= proc_dointvec_minmax,
1241 		.extra1		= &zero,
1242 		.extra2		= &two,
1243 	},
1244 	{
1245 		.procname	= "oom_kill_allocating_task",
1246 		.data		= &sysctl_oom_kill_allocating_task,
1247 		.maxlen		= sizeof(sysctl_oom_kill_allocating_task),
1248 		.mode		= 0644,
1249 		.proc_handler	= proc_dointvec,
1250 	},
1251 	{
1252 		.procname	= "oom_dump_tasks",
1253 		.data		= &sysctl_oom_dump_tasks,
1254 		.maxlen		= sizeof(sysctl_oom_dump_tasks),
1255 		.mode		= 0644,
1256 		.proc_handler	= proc_dointvec,
1257 	},
1258 	{
1259 		.procname	= "overcommit_ratio",
1260 		.data		= &sysctl_overcommit_ratio,
1261 		.maxlen		= sizeof(sysctl_overcommit_ratio),
1262 		.mode		= 0644,
1263 		.proc_handler	= overcommit_ratio_handler,
1264 	},
1265 	{
1266 		.procname	= "overcommit_kbytes",
1267 		.data		= &sysctl_overcommit_kbytes,
1268 		.maxlen		= sizeof(sysctl_overcommit_kbytes),
1269 		.mode		= 0644,
1270 		.proc_handler	= overcommit_kbytes_handler,
1271 	},
1272 	{
1273 		.procname	= "page-cluster",
1274 		.data		= &page_cluster,
1275 		.maxlen		= sizeof(int),
1276 		.mode		= 0644,
1277 		.proc_handler	= proc_dointvec_minmax,
1278 		.extra1		= &zero,
1279 	},
1280 	{
1281 		.procname	= "dirty_background_ratio",
1282 		.data		= &dirty_background_ratio,
1283 		.maxlen		= sizeof(dirty_background_ratio),
1284 		.mode		= 0644,
1285 		.proc_handler	= dirty_background_ratio_handler,
1286 		.extra1		= &zero,
1287 		.extra2		= &one_hundred,
1288 	},
1289 	{
1290 		.procname	= "dirty_background_bytes",
1291 		.data		= &dirty_background_bytes,
1292 		.maxlen		= sizeof(dirty_background_bytes),
1293 		.mode		= 0644,
1294 		.proc_handler	= dirty_background_bytes_handler,
1295 		.extra1		= &one_ul,
1296 	},
1297 	{
1298 		.procname	= "dirty_ratio",
1299 		.data		= &vm_dirty_ratio,
1300 		.maxlen		= sizeof(vm_dirty_ratio),
1301 		.mode		= 0644,
1302 		.proc_handler	= dirty_ratio_handler,
1303 		.extra1		= &zero,
1304 		.extra2		= &one_hundred,
1305 	},
1306 	{
1307 		.procname	= "dirty_bytes",
1308 		.data		= &vm_dirty_bytes,
1309 		.maxlen		= sizeof(vm_dirty_bytes),
1310 		.mode		= 0644,
1311 		.proc_handler	= dirty_bytes_handler,
1312 		.extra1		= &dirty_bytes_min,
1313 	},
1314 	{
1315 		.procname	= "dirty_writeback_centisecs",
1316 		.data		= &dirty_writeback_interval,
1317 		.maxlen		= sizeof(dirty_writeback_interval),
1318 		.mode		= 0644,
1319 		.proc_handler	= dirty_writeback_centisecs_handler,
1320 	},
1321 	{
1322 		.procname	= "dirty_expire_centisecs",
1323 		.data		= &dirty_expire_interval,
1324 		.maxlen		= sizeof(dirty_expire_interval),
1325 		.mode		= 0644,
1326 		.proc_handler	= proc_dointvec_minmax,
1327 		.extra1		= &zero,
1328 	},
1329 	{
1330 		.procname	= "dirtytime_expire_seconds",
1331 		.data		= &dirtytime_expire_interval,
1332 		.maxlen		= sizeof(dirty_expire_interval),
1333 		.mode		= 0644,
1334 		.proc_handler	= dirtytime_interval_handler,
1335 		.extra1		= &zero,
1336 	},
1337 	{
1338 		.procname	= "swappiness",
1339 		.data		= &vm_swappiness,
1340 		.maxlen		= sizeof(vm_swappiness),
1341 		.mode		= 0644,
1342 		.proc_handler	= proc_dointvec_minmax,
1343 		.extra1		= &zero,
1344 		.extra2		= &one_hundred,
1345 	},
1346 #ifdef CONFIG_HUGETLB_PAGE
1347 	{
1348 		.procname	= "nr_hugepages",
1349 		.data		= NULL,
1350 		.maxlen		= sizeof(unsigned long),
1351 		.mode		= 0644,
1352 		.proc_handler	= hugetlb_sysctl_handler,
1353 	},
1354 #ifdef CONFIG_NUMA
1355 	{
1356 		.procname       = "nr_hugepages_mempolicy",
1357 		.data           = NULL,
1358 		.maxlen         = sizeof(unsigned long),
1359 		.mode           = 0644,
1360 		.proc_handler   = &hugetlb_mempolicy_sysctl_handler,
1361 	},
1362 	{
1363 		.procname		= "numa_stat",
1364 		.data			= &sysctl_vm_numa_stat,
1365 		.maxlen			= sizeof(int),
1366 		.mode			= 0644,
1367 		.proc_handler	= sysctl_vm_numa_stat_handler,
1368 		.extra1			= &zero,
1369 		.extra2			= &one,
1370 	},
1371 #endif
1372 	 {
1373 		.procname	= "hugetlb_shm_group",
1374 		.data		= &sysctl_hugetlb_shm_group,
1375 		.maxlen		= sizeof(gid_t),
1376 		.mode		= 0644,
1377 		.proc_handler	= proc_dointvec,
1378 	 },
1379 	{
1380 		.procname	= "nr_overcommit_hugepages",
1381 		.data		= NULL,
1382 		.maxlen		= sizeof(unsigned long),
1383 		.mode		= 0644,
1384 		.proc_handler	= hugetlb_overcommit_handler,
1385 	},
1386 #endif
1387 	{
1388 		.procname	= "lowmem_reserve_ratio",
1389 		.data		= &sysctl_lowmem_reserve_ratio,
1390 		.maxlen		= sizeof(sysctl_lowmem_reserve_ratio),
1391 		.mode		= 0644,
1392 		.proc_handler	= lowmem_reserve_ratio_sysctl_handler,
1393 	},
1394 	{
1395 		.procname	= "drop_caches",
1396 		.data		= &sysctl_drop_caches,
1397 		.maxlen		= sizeof(int),
1398 		.mode		= 0644,
1399 		.proc_handler	= drop_caches_sysctl_handler,
1400 		.extra1		= &one,
1401 		.extra2		= &four,
1402 	},
1403 #ifdef CONFIG_COMPACTION
1404 	{
1405 		.procname	= "compact_memory",
1406 		.data		= &sysctl_compact_memory,
1407 		.maxlen		= sizeof(int),
1408 		.mode		= 0200,
1409 		.proc_handler	= sysctl_compaction_handler,
1410 	},
1411 	{
1412 		.procname	= "extfrag_threshold",
1413 		.data		= &sysctl_extfrag_threshold,
1414 		.maxlen		= sizeof(int),
1415 		.mode		= 0644,
1416 		.proc_handler	= sysctl_extfrag_handler,
1417 		.extra1		= &min_extfrag_threshold,
1418 		.extra2		= &max_extfrag_threshold,
1419 	},
1420 	{
1421 		.procname	= "compact_unevictable_allowed",
1422 		.data		= &sysctl_compact_unevictable_allowed,
1423 		.maxlen		= sizeof(int),
1424 		.mode		= 0644,
1425 		.proc_handler	= proc_dointvec,
1426 		.extra1		= &zero,
1427 		.extra2		= &one,
1428 	},
1429 
1430 #endif /* CONFIG_COMPACTION */
1431 	{
1432 		.procname	= "min_free_kbytes",
1433 		.data		= &min_free_kbytes,
1434 		.maxlen		= sizeof(min_free_kbytes),
1435 		.mode		= 0644,
1436 		.proc_handler	= min_free_kbytes_sysctl_handler,
1437 		.extra1		= &zero,
1438 	},
1439 	{
1440 		.procname	= "watermark_scale_factor",
1441 		.data		= &watermark_scale_factor,
1442 		.maxlen		= sizeof(watermark_scale_factor),
1443 		.mode		= 0644,
1444 		.proc_handler	= watermark_scale_factor_sysctl_handler,
1445 		.extra1		= &one,
1446 		.extra2		= &one_thousand,
1447 	},
1448 	{
1449 		.procname	= "percpu_pagelist_fraction",
1450 		.data		= &percpu_pagelist_fraction,
1451 		.maxlen		= sizeof(percpu_pagelist_fraction),
1452 		.mode		= 0644,
1453 		.proc_handler	= percpu_pagelist_fraction_sysctl_handler,
1454 		.extra1		= &zero,
1455 	},
1456 #ifdef CONFIG_MMU
1457 	{
1458 		.procname	= "max_map_count",
1459 		.data		= &sysctl_max_map_count,
1460 		.maxlen		= sizeof(sysctl_max_map_count),
1461 		.mode		= 0644,
1462 		.proc_handler	= proc_dointvec_minmax,
1463 		.extra1		= &zero,
1464 	},
1465 #else
1466 	{
1467 		.procname	= "nr_trim_pages",
1468 		.data		= &sysctl_nr_trim_pages,
1469 		.maxlen		= sizeof(sysctl_nr_trim_pages),
1470 		.mode		= 0644,
1471 		.proc_handler	= proc_dointvec_minmax,
1472 		.extra1		= &zero,
1473 	},
1474 #endif
1475 	{
1476 		.procname	= "laptop_mode",
1477 		.data		= &laptop_mode,
1478 		.maxlen		= sizeof(laptop_mode),
1479 		.mode		= 0644,
1480 		.proc_handler	= proc_dointvec_jiffies,
1481 	},
1482 	{
1483 		.procname	= "block_dump",
1484 		.data		= &block_dump,
1485 		.maxlen		= sizeof(block_dump),
1486 		.mode		= 0644,
1487 		.proc_handler	= proc_dointvec,
1488 		.extra1		= &zero,
1489 	},
1490 	{
1491 		.procname	= "vfs_cache_pressure",
1492 		.data		= &sysctl_vfs_cache_pressure,
1493 		.maxlen		= sizeof(sysctl_vfs_cache_pressure),
1494 		.mode		= 0644,
1495 		.proc_handler	= proc_dointvec,
1496 		.extra1		= &zero,
1497 	},
1498 #ifdef HAVE_ARCH_PICK_MMAP_LAYOUT
1499 	{
1500 		.procname	= "legacy_va_layout",
1501 		.data		= &sysctl_legacy_va_layout,
1502 		.maxlen		= sizeof(sysctl_legacy_va_layout),
1503 		.mode		= 0644,
1504 		.proc_handler	= proc_dointvec,
1505 		.extra1		= &zero,
1506 	},
1507 #endif
1508 #ifdef CONFIG_NUMA
1509 	{
1510 		.procname	= "zone_reclaim_mode",
1511 		.data		= &node_reclaim_mode,
1512 		.maxlen		= sizeof(node_reclaim_mode),
1513 		.mode		= 0644,
1514 		.proc_handler	= proc_dointvec,
1515 		.extra1		= &zero,
1516 	},
1517 	{
1518 		.procname	= "min_unmapped_ratio",
1519 		.data		= &sysctl_min_unmapped_ratio,
1520 		.maxlen		= sizeof(sysctl_min_unmapped_ratio),
1521 		.mode		= 0644,
1522 		.proc_handler	= sysctl_min_unmapped_ratio_sysctl_handler,
1523 		.extra1		= &zero,
1524 		.extra2		= &one_hundred,
1525 	},
1526 	{
1527 		.procname	= "min_slab_ratio",
1528 		.data		= &sysctl_min_slab_ratio,
1529 		.maxlen		= sizeof(sysctl_min_slab_ratio),
1530 		.mode		= 0644,
1531 		.proc_handler	= sysctl_min_slab_ratio_sysctl_handler,
1532 		.extra1		= &zero,
1533 		.extra2		= &one_hundred,
1534 	},
1535 #endif
1536 #ifdef CONFIG_SMP
1537 	{
1538 		.procname	= "stat_interval",
1539 		.data		= &sysctl_stat_interval,
1540 		.maxlen		= sizeof(sysctl_stat_interval),
1541 		.mode		= 0644,
1542 		.proc_handler	= proc_dointvec_jiffies,
1543 	},
1544 	{
1545 		.procname	= "stat_refresh",
1546 		.data		= NULL,
1547 		.maxlen		= 0,
1548 		.mode		= 0600,
1549 		.proc_handler	= vmstat_refresh,
1550 	},
1551 #endif
1552 #ifdef CONFIG_MMU
1553 	{
1554 		.procname	= "mmap_min_addr",
1555 		.data		= &dac_mmap_min_addr,
1556 		.maxlen		= sizeof(unsigned long),
1557 		.mode		= 0644,
1558 		.proc_handler	= mmap_min_addr_handler,
1559 	},
1560 #endif
1561 #ifdef CONFIG_NUMA
1562 	{
1563 		.procname	= "numa_zonelist_order",
1564 		.data		= &numa_zonelist_order,
1565 		.maxlen		= NUMA_ZONELIST_ORDER_LEN,
1566 		.mode		= 0644,
1567 		.proc_handler	= numa_zonelist_order_handler,
1568 	},
1569 #endif
1570 #if (defined(CONFIG_X86_32) && !defined(CONFIG_UML))|| \
1571    (defined(CONFIG_SUPERH) && defined(CONFIG_VSYSCALL))
1572 	{
1573 		.procname	= "vdso_enabled",
1574 #ifdef CONFIG_X86_32
1575 		.data		= &vdso32_enabled,
1576 		.maxlen		= sizeof(vdso32_enabled),
1577 #else
1578 		.data		= &vdso_enabled,
1579 		.maxlen		= sizeof(vdso_enabled),
1580 #endif
1581 		.mode		= 0644,
1582 		.proc_handler	= proc_dointvec,
1583 		.extra1		= &zero,
1584 	},
1585 #endif
1586 #ifdef CONFIG_HIGHMEM
1587 	{
1588 		.procname	= "highmem_is_dirtyable",
1589 		.data		= &vm_highmem_is_dirtyable,
1590 		.maxlen		= sizeof(vm_highmem_is_dirtyable),
1591 		.mode		= 0644,
1592 		.proc_handler	= proc_dointvec_minmax,
1593 		.extra1		= &zero,
1594 		.extra2		= &one,
1595 	},
1596 #endif
1597 #ifdef CONFIG_MEMORY_FAILURE
1598 	{
1599 		.procname	= "memory_failure_early_kill",
1600 		.data		= &sysctl_memory_failure_early_kill,
1601 		.maxlen		= sizeof(sysctl_memory_failure_early_kill),
1602 		.mode		= 0644,
1603 		.proc_handler	= proc_dointvec_minmax,
1604 		.extra1		= &zero,
1605 		.extra2		= &one,
1606 	},
1607 	{
1608 		.procname	= "memory_failure_recovery",
1609 		.data		= &sysctl_memory_failure_recovery,
1610 		.maxlen		= sizeof(sysctl_memory_failure_recovery),
1611 		.mode		= 0644,
1612 		.proc_handler	= proc_dointvec_minmax,
1613 		.extra1		= &zero,
1614 		.extra2		= &one,
1615 	},
1616 #endif
1617 	{
1618 		.procname	= "user_reserve_kbytes",
1619 		.data		= &sysctl_user_reserve_kbytes,
1620 		.maxlen		= sizeof(sysctl_user_reserve_kbytes),
1621 		.mode		= 0644,
1622 		.proc_handler	= proc_doulongvec_minmax,
1623 	},
1624 	{
1625 		.procname	= "admin_reserve_kbytes",
1626 		.data		= &sysctl_admin_reserve_kbytes,
1627 		.maxlen		= sizeof(sysctl_admin_reserve_kbytes),
1628 		.mode		= 0644,
1629 		.proc_handler	= proc_doulongvec_minmax,
1630 	},
1631 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_BITS
1632 	{
1633 		.procname	= "mmap_rnd_bits",
1634 		.data		= &mmap_rnd_bits,
1635 		.maxlen		= sizeof(mmap_rnd_bits),
1636 		.mode		= 0600,
1637 		.proc_handler	= proc_dointvec_minmax,
1638 		.extra1		= (void *)&mmap_rnd_bits_min,
1639 		.extra2		= (void *)&mmap_rnd_bits_max,
1640 	},
1641 #endif
1642 #ifdef CONFIG_HAVE_ARCH_MMAP_RND_COMPAT_BITS
1643 	{
1644 		.procname	= "mmap_rnd_compat_bits",
1645 		.data		= &mmap_rnd_compat_bits,
1646 		.maxlen		= sizeof(mmap_rnd_compat_bits),
1647 		.mode		= 0600,
1648 		.proc_handler	= proc_dointvec_minmax,
1649 		.extra1		= (void *)&mmap_rnd_compat_bits_min,
1650 		.extra2		= (void *)&mmap_rnd_compat_bits_max,
1651 	},
1652 #endif
1653 	{ }
1654 };
1655 
1656 static struct ctl_table fs_table[] = {
1657 	{
1658 		.procname	= "inode-nr",
1659 		.data		= &inodes_stat,
1660 		.maxlen		= 2*sizeof(long),
1661 		.mode		= 0444,
1662 		.proc_handler	= proc_nr_inodes,
1663 	},
1664 	{
1665 		.procname	= "inode-state",
1666 		.data		= &inodes_stat,
1667 		.maxlen		= 7*sizeof(long),
1668 		.mode		= 0444,
1669 		.proc_handler	= proc_nr_inodes,
1670 	},
1671 	{
1672 		.procname	= "file-nr",
1673 		.data		= &files_stat,
1674 		.maxlen		= sizeof(files_stat),
1675 		.mode		= 0444,
1676 		.proc_handler	= proc_nr_files,
1677 	},
1678 	{
1679 		.procname	= "file-max",
1680 		.data		= &files_stat.max_files,
1681 		.maxlen		= sizeof(files_stat.max_files),
1682 		.mode		= 0644,
1683 		.proc_handler	= proc_doulongvec_minmax,
1684 	},
1685 	{
1686 		.procname	= "nr_open",
1687 		.data		= &sysctl_nr_open,
1688 		.maxlen		= sizeof(unsigned int),
1689 		.mode		= 0644,
1690 		.proc_handler	= proc_dointvec_minmax,
1691 		.extra1		= &sysctl_nr_open_min,
1692 		.extra2		= &sysctl_nr_open_max,
1693 	},
1694 	{
1695 		.procname	= "dentry-state",
1696 		.data		= &dentry_stat,
1697 		.maxlen		= 6*sizeof(long),
1698 		.mode		= 0444,
1699 		.proc_handler	= proc_nr_dentry,
1700 	},
1701 	{
1702 		.procname	= "overflowuid",
1703 		.data		= &fs_overflowuid,
1704 		.maxlen		= sizeof(int),
1705 		.mode		= 0644,
1706 		.proc_handler	= proc_dointvec_minmax,
1707 		.extra1		= &minolduid,
1708 		.extra2		= &maxolduid,
1709 	},
1710 	{
1711 		.procname	= "overflowgid",
1712 		.data		= &fs_overflowgid,
1713 		.maxlen		= sizeof(int),
1714 		.mode		= 0644,
1715 		.proc_handler	= proc_dointvec_minmax,
1716 		.extra1		= &minolduid,
1717 		.extra2		= &maxolduid,
1718 	},
1719 #ifdef CONFIG_FILE_LOCKING
1720 	{
1721 		.procname	= "leases-enable",
1722 		.data		= &leases_enable,
1723 		.maxlen		= sizeof(int),
1724 		.mode		= 0644,
1725 		.proc_handler	= proc_dointvec,
1726 	},
1727 #endif
1728 #ifdef CONFIG_DNOTIFY
1729 	{
1730 		.procname	= "dir-notify-enable",
1731 		.data		= &dir_notify_enable,
1732 		.maxlen		= sizeof(int),
1733 		.mode		= 0644,
1734 		.proc_handler	= proc_dointvec,
1735 	},
1736 #endif
1737 #ifdef CONFIG_MMU
1738 #ifdef CONFIG_FILE_LOCKING
1739 	{
1740 		.procname	= "lease-break-time",
1741 		.data		= &lease_break_time,
1742 		.maxlen		= sizeof(int),
1743 		.mode		= 0644,
1744 		.proc_handler	= proc_dointvec,
1745 	},
1746 #endif
1747 #ifdef CONFIG_AIO
1748 	{
1749 		.procname	= "aio-nr",
1750 		.data		= &aio_nr,
1751 		.maxlen		= sizeof(aio_nr),
1752 		.mode		= 0444,
1753 		.proc_handler	= proc_doulongvec_minmax,
1754 	},
1755 	{
1756 		.procname	= "aio-max-nr",
1757 		.data		= &aio_max_nr,
1758 		.maxlen		= sizeof(aio_max_nr),
1759 		.mode		= 0644,
1760 		.proc_handler	= proc_doulongvec_minmax,
1761 	},
1762 #endif /* CONFIG_AIO */
1763 #ifdef CONFIG_INOTIFY_USER
1764 	{
1765 		.procname	= "inotify",
1766 		.mode		= 0555,
1767 		.child		= inotify_table,
1768 	},
1769 #endif
1770 #ifdef CONFIG_EPOLL
1771 	{
1772 		.procname	= "epoll",
1773 		.mode		= 0555,
1774 		.child		= epoll_table,
1775 	},
1776 #endif
1777 #endif
1778 	{
1779 		.procname	= "protected_symlinks",
1780 		.data		= &sysctl_protected_symlinks,
1781 		.maxlen		= sizeof(int),
1782 		.mode		= 0600,
1783 		.proc_handler	= proc_dointvec_minmax,
1784 		.extra1		= &zero,
1785 		.extra2		= &one,
1786 	},
1787 	{
1788 		.procname	= "protected_hardlinks",
1789 		.data		= &sysctl_protected_hardlinks,
1790 		.maxlen		= sizeof(int),
1791 		.mode		= 0600,
1792 		.proc_handler	= proc_dointvec_minmax,
1793 		.extra1		= &zero,
1794 		.extra2		= &one,
1795 	},
1796 	{
1797 		.procname	= "suid_dumpable",
1798 		.data		= &suid_dumpable,
1799 		.maxlen		= sizeof(int),
1800 		.mode		= 0644,
1801 		.proc_handler	= proc_dointvec_minmax_coredump,
1802 		.extra1		= &zero,
1803 		.extra2		= &two,
1804 	},
1805 #if defined(CONFIG_BINFMT_MISC) || defined(CONFIG_BINFMT_MISC_MODULE)
1806 	{
1807 		.procname	= "binfmt_misc",
1808 		.mode		= 0555,
1809 		.child		= sysctl_mount_point,
1810 	},
1811 #endif
1812 	{
1813 		.procname	= "pipe-max-size",
1814 		.data		= &pipe_max_size,
1815 		.maxlen		= sizeof(pipe_max_size),
1816 		.mode		= 0644,
1817 		.proc_handler	= proc_dopipe_max_size,
1818 	},
1819 	{
1820 		.procname	= "pipe-user-pages-hard",
1821 		.data		= &pipe_user_pages_hard,
1822 		.maxlen		= sizeof(pipe_user_pages_hard),
1823 		.mode		= 0644,
1824 		.proc_handler	= proc_doulongvec_minmax,
1825 	},
1826 	{
1827 		.procname	= "pipe-user-pages-soft",
1828 		.data		= &pipe_user_pages_soft,
1829 		.maxlen		= sizeof(pipe_user_pages_soft),
1830 		.mode		= 0644,
1831 		.proc_handler	= proc_doulongvec_minmax,
1832 	},
1833 	{
1834 		.procname	= "mount-max",
1835 		.data		= &sysctl_mount_max,
1836 		.maxlen		= sizeof(unsigned int),
1837 		.mode		= 0644,
1838 		.proc_handler	= proc_dointvec_minmax,
1839 		.extra1		= &one,
1840 	},
1841 	{ }
1842 };
1843 
1844 static struct ctl_table debug_table[] = {
1845 #ifdef CONFIG_SYSCTL_EXCEPTION_TRACE
1846 	{
1847 		.procname	= "exception-trace",
1848 		.data		= &show_unhandled_signals,
1849 		.maxlen		= sizeof(int),
1850 		.mode		= 0644,
1851 		.proc_handler	= proc_dointvec
1852 	},
1853 #endif
1854 #if defined(CONFIG_OPTPROBES)
1855 	{
1856 		.procname	= "kprobes-optimization",
1857 		.data		= &sysctl_kprobes_optimization,
1858 		.maxlen		= sizeof(int),
1859 		.mode		= 0644,
1860 		.proc_handler	= proc_kprobes_optimization_handler,
1861 		.extra1		= &zero,
1862 		.extra2		= &one,
1863 	},
1864 #endif
1865 	{ }
1866 };
1867 
1868 static struct ctl_table dev_table[] = {
1869 	{ }
1870 };
1871 
1872 int __init sysctl_init(void)
1873 {
1874 	struct ctl_table_header *hdr;
1875 
1876 	hdr = register_sysctl_table(sysctl_base_table);
1877 	kmemleak_not_leak(hdr);
1878 	return 0;
1879 }
1880 
1881 #endif /* CONFIG_SYSCTL */
1882 
1883 /*
1884  * /proc/sys support
1885  */
1886 
1887 #ifdef CONFIG_PROC_SYSCTL
1888 
1889 static int _proc_do_string(char *data, int maxlen, int write,
1890 			   char __user *buffer,
1891 			   size_t *lenp, loff_t *ppos)
1892 {
1893 	size_t len;
1894 	char __user *p;
1895 	char c;
1896 
1897 	if (!data || !maxlen || !*lenp) {
1898 		*lenp = 0;
1899 		return 0;
1900 	}
1901 
1902 	if (write) {
1903 		if (sysctl_writes_strict == SYSCTL_WRITES_STRICT) {
1904 			/* Only continue writes not past the end of buffer. */
1905 			len = strlen(data);
1906 			if (len > maxlen - 1)
1907 				len = maxlen - 1;
1908 
1909 			if (*ppos > len)
1910 				return 0;
1911 			len = *ppos;
1912 		} else {
1913 			/* Start writing from beginning of buffer. */
1914 			len = 0;
1915 		}
1916 
1917 		*ppos += *lenp;
1918 		p = buffer;
1919 		while ((p - buffer) < *lenp && len < maxlen - 1) {
1920 			if (get_user(c, p++))
1921 				return -EFAULT;
1922 			if (c == 0 || c == '\n')
1923 				break;
1924 			data[len++] = c;
1925 		}
1926 		data[len] = 0;
1927 	} else {
1928 		len = strlen(data);
1929 		if (len > maxlen)
1930 			len = maxlen;
1931 
1932 		if (*ppos > len) {
1933 			*lenp = 0;
1934 			return 0;
1935 		}
1936 
1937 		data += *ppos;
1938 		len  -= *ppos;
1939 
1940 		if (len > *lenp)
1941 			len = *lenp;
1942 		if (len)
1943 			if (copy_to_user(buffer, data, len))
1944 				return -EFAULT;
1945 		if (len < *lenp) {
1946 			if (put_user('\n', buffer + len))
1947 				return -EFAULT;
1948 			len++;
1949 		}
1950 		*lenp = len;
1951 		*ppos += len;
1952 	}
1953 	return 0;
1954 }
1955 
1956 static void warn_sysctl_write(struct ctl_table *table)
1957 {
1958 	pr_warn_once("%s wrote to %s when file position was not 0!\n"
1959 		"This will not be supported in the future. To silence this\n"
1960 		"warning, set kernel.sysctl_writes_strict = -1\n",
1961 		current->comm, table->procname);
1962 }
1963 
1964 /**
1965  * proc_first_pos_non_zero_ignore - check if firs position is allowed
1966  * @ppos: file position
1967  * @table: the sysctl table
1968  *
1969  * Returns true if the first position is non-zero and the sysctl_writes_strict
1970  * mode indicates this is not allowed for numeric input types. String proc
1971  * hadlers can ignore the return value.
1972  */
1973 static bool proc_first_pos_non_zero_ignore(loff_t *ppos,
1974 					   struct ctl_table *table)
1975 {
1976 	if (!*ppos)
1977 		return false;
1978 
1979 	switch (sysctl_writes_strict) {
1980 	case SYSCTL_WRITES_STRICT:
1981 		return true;
1982 	case SYSCTL_WRITES_WARN:
1983 		warn_sysctl_write(table);
1984 		return false;
1985 	default:
1986 		return false;
1987 	}
1988 }
1989 
1990 /**
1991  * proc_dostring - read a string sysctl
1992  * @table: the sysctl table
1993  * @write: %TRUE if this is a write to the sysctl file
1994  * @buffer: the user buffer
1995  * @lenp: the size of the user buffer
1996  * @ppos: file position
1997  *
1998  * Reads/writes a string from/to the user buffer. If the kernel
1999  * buffer provided is not large enough to hold the string, the
2000  * string is truncated. The copied string is %NULL-terminated.
2001  * If the string is being read by the user process, it is copied
2002  * and a newline '\n' is added. It is truncated if the buffer is
2003  * not large enough.
2004  *
2005  * Returns 0 on success.
2006  */
2007 int proc_dostring(struct ctl_table *table, int write,
2008 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2009 {
2010 	if (write)
2011 		proc_first_pos_non_zero_ignore(ppos, table);
2012 
2013 	return _proc_do_string((char *)(table->data), table->maxlen, write,
2014 			       (char __user *)buffer, lenp, ppos);
2015 }
2016 
2017 static size_t proc_skip_spaces(char **buf)
2018 {
2019 	size_t ret;
2020 	char *tmp = skip_spaces(*buf);
2021 	ret = tmp - *buf;
2022 	*buf = tmp;
2023 	return ret;
2024 }
2025 
2026 static void proc_skip_char(char **buf, size_t *size, const char v)
2027 {
2028 	while (*size) {
2029 		if (**buf != v)
2030 			break;
2031 		(*size)--;
2032 		(*buf)++;
2033 	}
2034 }
2035 
2036 #define TMPBUFLEN 22
2037 /**
2038  * proc_get_long - reads an ASCII formatted integer from a user buffer
2039  *
2040  * @buf: a kernel buffer
2041  * @size: size of the kernel buffer
2042  * @val: this is where the number will be stored
2043  * @neg: set to %TRUE if number is negative
2044  * @perm_tr: a vector which contains the allowed trailers
2045  * @perm_tr_len: size of the perm_tr vector
2046  * @tr: pointer to store the trailer character
2047  *
2048  * In case of success %0 is returned and @buf and @size are updated with
2049  * the amount of bytes read. If @tr is non-NULL and a trailing
2050  * character exists (size is non-zero after returning from this
2051  * function), @tr is updated with the trailing character.
2052  */
2053 static int proc_get_long(char **buf, size_t *size,
2054 			  unsigned long *val, bool *neg,
2055 			  const char *perm_tr, unsigned perm_tr_len, char *tr)
2056 {
2057 	int len;
2058 	char *p, tmp[TMPBUFLEN];
2059 
2060 	if (!*size)
2061 		return -EINVAL;
2062 
2063 	len = *size;
2064 	if (len > TMPBUFLEN - 1)
2065 		len = TMPBUFLEN - 1;
2066 
2067 	memcpy(tmp, *buf, len);
2068 
2069 	tmp[len] = 0;
2070 	p = tmp;
2071 	if (*p == '-' && *size > 1) {
2072 		*neg = true;
2073 		p++;
2074 	} else
2075 		*neg = false;
2076 	if (!isdigit(*p))
2077 		return -EINVAL;
2078 
2079 	*val = simple_strtoul(p, &p, 0);
2080 
2081 	len = p - tmp;
2082 
2083 	/* We don't know if the next char is whitespace thus we may accept
2084 	 * invalid integers (e.g. 1234...a) or two integers instead of one
2085 	 * (e.g. 123...1). So lets not allow such large numbers. */
2086 	if (len == TMPBUFLEN - 1)
2087 		return -EINVAL;
2088 
2089 	if (len < *size && perm_tr_len && !memchr(perm_tr, *p, perm_tr_len))
2090 		return -EINVAL;
2091 
2092 	if (tr && (len < *size))
2093 		*tr = *p;
2094 
2095 	*buf += len;
2096 	*size -= len;
2097 
2098 	return 0;
2099 }
2100 
2101 /**
2102  * proc_put_long - converts an integer to a decimal ASCII formatted string
2103  *
2104  * @buf: the user buffer
2105  * @size: the size of the user buffer
2106  * @val: the integer to be converted
2107  * @neg: sign of the number, %TRUE for negative
2108  *
2109  * In case of success %0 is returned and @buf and @size are updated with
2110  * the amount of bytes written.
2111  */
2112 static int proc_put_long(void __user **buf, size_t *size, unsigned long val,
2113 			  bool neg)
2114 {
2115 	int len;
2116 	char tmp[TMPBUFLEN], *p = tmp;
2117 
2118 	sprintf(p, "%s%lu", neg ? "-" : "", val);
2119 	len = strlen(tmp);
2120 	if (len > *size)
2121 		len = *size;
2122 	if (copy_to_user(*buf, tmp, len))
2123 		return -EFAULT;
2124 	*size -= len;
2125 	*buf += len;
2126 	return 0;
2127 }
2128 #undef TMPBUFLEN
2129 
2130 static int proc_put_char(void __user **buf, size_t *size, char c)
2131 {
2132 	if (*size) {
2133 		char __user **buffer = (char __user **)buf;
2134 		if (put_user(c, *buffer))
2135 			return -EFAULT;
2136 		(*size)--, (*buffer)++;
2137 		*buf = *buffer;
2138 	}
2139 	return 0;
2140 }
2141 
2142 static int do_proc_dointvec_conv(bool *negp, unsigned long *lvalp,
2143 				 int *valp,
2144 				 int write, void *data)
2145 {
2146 	if (write) {
2147 		if (*negp) {
2148 			if (*lvalp > (unsigned long) INT_MAX + 1)
2149 				return -EINVAL;
2150 			*valp = -*lvalp;
2151 		} else {
2152 			if (*lvalp > (unsigned long) INT_MAX)
2153 				return -EINVAL;
2154 			*valp = *lvalp;
2155 		}
2156 	} else {
2157 		int val = *valp;
2158 		if (val < 0) {
2159 			*negp = true;
2160 			*lvalp = -(unsigned long)val;
2161 		} else {
2162 			*negp = false;
2163 			*lvalp = (unsigned long)val;
2164 		}
2165 	}
2166 	return 0;
2167 }
2168 
2169 static int do_proc_douintvec_conv(unsigned long *lvalp,
2170 				  unsigned int *valp,
2171 				  int write, void *data)
2172 {
2173 	if (write) {
2174 		if (*lvalp > UINT_MAX)
2175 			return -EINVAL;
2176 		*valp = *lvalp;
2177 	} else {
2178 		unsigned int val = *valp;
2179 		*lvalp = (unsigned long)val;
2180 	}
2181 	return 0;
2182 }
2183 
2184 static const char proc_wspace_sep[] = { ' ', '\t', '\n' };
2185 
2186 static int __do_proc_dointvec(void *tbl_data, struct ctl_table *table,
2187 		  int write, void __user *buffer,
2188 		  size_t *lenp, loff_t *ppos,
2189 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2190 			      int write, void *data),
2191 		  void *data)
2192 {
2193 	int *i, vleft, first = 1, err = 0;
2194 	size_t left;
2195 	char *kbuf = NULL, *p;
2196 
2197 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2198 		*lenp = 0;
2199 		return 0;
2200 	}
2201 
2202 	i = (int *) tbl_data;
2203 	vleft = table->maxlen / sizeof(*i);
2204 	left = *lenp;
2205 
2206 	if (!conv)
2207 		conv = do_proc_dointvec_conv;
2208 
2209 	if (write) {
2210 		if (proc_first_pos_non_zero_ignore(ppos, table))
2211 			goto out;
2212 
2213 		if (left > PAGE_SIZE - 1)
2214 			left = PAGE_SIZE - 1;
2215 		p = kbuf = memdup_user_nul(buffer, left);
2216 		if (IS_ERR(kbuf))
2217 			return PTR_ERR(kbuf);
2218 	}
2219 
2220 	for (; left && vleft--; i++, first=0) {
2221 		unsigned long lval;
2222 		bool neg;
2223 
2224 		if (write) {
2225 			left -= proc_skip_spaces(&p);
2226 
2227 			if (!left)
2228 				break;
2229 			err = proc_get_long(&p, &left, &lval, &neg,
2230 					     proc_wspace_sep,
2231 					     sizeof(proc_wspace_sep), NULL);
2232 			if (err)
2233 				break;
2234 			if (conv(&neg, &lval, i, 1, data)) {
2235 				err = -EINVAL;
2236 				break;
2237 			}
2238 		} else {
2239 			if (conv(&neg, &lval, i, 0, data)) {
2240 				err = -EINVAL;
2241 				break;
2242 			}
2243 			if (!first)
2244 				err = proc_put_char(&buffer, &left, '\t');
2245 			if (err)
2246 				break;
2247 			err = proc_put_long(&buffer, &left, lval, neg);
2248 			if (err)
2249 				break;
2250 		}
2251 	}
2252 
2253 	if (!write && !first && left && !err)
2254 		err = proc_put_char(&buffer, &left, '\n');
2255 	if (write && !err && left)
2256 		left -= proc_skip_spaces(&p);
2257 	if (write) {
2258 		kfree(kbuf);
2259 		if (first)
2260 			return err ? : -EINVAL;
2261 	}
2262 	*lenp -= left;
2263 out:
2264 	*ppos += *lenp;
2265 	return err;
2266 }
2267 
2268 static int do_proc_dointvec(struct ctl_table *table, int write,
2269 		  void __user *buffer, size_t *lenp, loff_t *ppos,
2270 		  int (*conv)(bool *negp, unsigned long *lvalp, int *valp,
2271 			      int write, void *data),
2272 		  void *data)
2273 {
2274 	return __do_proc_dointvec(table->data, table, write,
2275 			buffer, lenp, ppos, conv, data);
2276 }
2277 
2278 static int do_proc_douintvec_w(unsigned int *tbl_data,
2279 			       struct ctl_table *table,
2280 			       void __user *buffer,
2281 			       size_t *lenp, loff_t *ppos,
2282 			       int (*conv)(unsigned long *lvalp,
2283 					   unsigned int *valp,
2284 					   int write, void *data),
2285 			       void *data)
2286 {
2287 	unsigned long lval;
2288 	int err = 0;
2289 	size_t left;
2290 	bool neg;
2291 	char *kbuf = NULL, *p;
2292 
2293 	left = *lenp;
2294 
2295 	if (proc_first_pos_non_zero_ignore(ppos, table))
2296 		goto bail_early;
2297 
2298 	if (left > PAGE_SIZE - 1)
2299 		left = PAGE_SIZE - 1;
2300 
2301 	p = kbuf = memdup_user_nul(buffer, left);
2302 	if (IS_ERR(kbuf))
2303 		return -EINVAL;
2304 
2305 	left -= proc_skip_spaces(&p);
2306 	if (!left) {
2307 		err = -EINVAL;
2308 		goto out_free;
2309 	}
2310 
2311 	err = proc_get_long(&p, &left, &lval, &neg,
2312 			     proc_wspace_sep,
2313 			     sizeof(proc_wspace_sep), NULL);
2314 	if (err || neg) {
2315 		err = -EINVAL;
2316 		goto out_free;
2317 	}
2318 
2319 	if (conv(&lval, tbl_data, 1, data)) {
2320 		err = -EINVAL;
2321 		goto out_free;
2322 	}
2323 
2324 	if (!err && left)
2325 		left -= proc_skip_spaces(&p);
2326 
2327 out_free:
2328 	kfree(kbuf);
2329 	if (err)
2330 		return -EINVAL;
2331 
2332 	return 0;
2333 
2334 	/* This is in keeping with old __do_proc_dointvec() */
2335 bail_early:
2336 	*ppos += *lenp;
2337 	return err;
2338 }
2339 
2340 static int do_proc_douintvec_r(unsigned int *tbl_data, void __user *buffer,
2341 			       size_t *lenp, loff_t *ppos,
2342 			       int (*conv)(unsigned long *lvalp,
2343 					   unsigned int *valp,
2344 					   int write, void *data),
2345 			       void *data)
2346 {
2347 	unsigned long lval;
2348 	int err = 0;
2349 	size_t left;
2350 
2351 	left = *lenp;
2352 
2353 	if (conv(&lval, tbl_data, 0, data)) {
2354 		err = -EINVAL;
2355 		goto out;
2356 	}
2357 
2358 	err = proc_put_long(&buffer, &left, lval, false);
2359 	if (err || !left)
2360 		goto out;
2361 
2362 	err = proc_put_char(&buffer, &left, '\n');
2363 
2364 out:
2365 	*lenp -= left;
2366 	*ppos += *lenp;
2367 
2368 	return err;
2369 }
2370 
2371 static int __do_proc_douintvec(void *tbl_data, struct ctl_table *table,
2372 			       int write, void __user *buffer,
2373 			       size_t *lenp, loff_t *ppos,
2374 			       int (*conv)(unsigned long *lvalp,
2375 					   unsigned int *valp,
2376 					   int write, void *data),
2377 			       void *data)
2378 {
2379 	unsigned int *i, vleft;
2380 
2381 	if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
2382 		*lenp = 0;
2383 		return 0;
2384 	}
2385 
2386 	i = (unsigned int *) tbl_data;
2387 	vleft = table->maxlen / sizeof(*i);
2388 
2389 	/*
2390 	 * Arrays are not supported, keep this simple. *Do not* add
2391 	 * support for them.
2392 	 */
2393 	if (vleft != 1) {
2394 		*lenp = 0;
2395 		return -EINVAL;
2396 	}
2397 
2398 	if (!conv)
2399 		conv = do_proc_douintvec_conv;
2400 
2401 	if (write)
2402 		return do_proc_douintvec_w(i, table, buffer, lenp, ppos,
2403 					   conv, data);
2404 	return do_proc_douintvec_r(i, buffer, lenp, ppos, conv, data);
2405 }
2406 
2407 static int do_proc_douintvec(struct ctl_table *table, int write,
2408 			     void __user *buffer, size_t *lenp, loff_t *ppos,
2409 			     int (*conv)(unsigned long *lvalp,
2410 					 unsigned int *valp,
2411 					 int write, void *data),
2412 			     void *data)
2413 {
2414 	return __do_proc_douintvec(table->data, table, write,
2415 				   buffer, lenp, ppos, conv, data);
2416 }
2417 
2418 /**
2419  * proc_dointvec - read a vector of integers
2420  * @table: the sysctl table
2421  * @write: %TRUE if this is a write to the sysctl file
2422  * @buffer: the user buffer
2423  * @lenp: the size of the user buffer
2424  * @ppos: file position
2425  *
2426  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2427  * values from/to the user buffer, treated as an ASCII string.
2428  *
2429  * Returns 0 on success.
2430  */
2431 int proc_dointvec(struct ctl_table *table, int write,
2432 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2433 {
2434 	return do_proc_dointvec(table, write, buffer, lenp, ppos, NULL, NULL);
2435 }
2436 
2437 /**
2438  * proc_douintvec - read a vector of unsigned integers
2439  * @table: the sysctl table
2440  * @write: %TRUE if this is a write to the sysctl file
2441  * @buffer: the user buffer
2442  * @lenp: the size of the user buffer
2443  * @ppos: file position
2444  *
2445  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2446  * values from/to the user buffer, treated as an ASCII string.
2447  *
2448  * Returns 0 on success.
2449  */
2450 int proc_douintvec(struct ctl_table *table, int write,
2451 		     void __user *buffer, size_t *lenp, loff_t *ppos)
2452 {
2453 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2454 				 do_proc_douintvec_conv, NULL);
2455 }
2456 
2457 /*
2458  * Taint values can only be increased
2459  * This means we can safely use a temporary.
2460  */
2461 static int proc_taint(struct ctl_table *table, int write,
2462 			       void __user *buffer, size_t *lenp, loff_t *ppos)
2463 {
2464 	struct ctl_table t;
2465 	unsigned long tmptaint = get_taint();
2466 	int err;
2467 
2468 	if (write && !capable(CAP_SYS_ADMIN))
2469 		return -EPERM;
2470 
2471 	t = *table;
2472 	t.data = &tmptaint;
2473 	err = proc_doulongvec_minmax(&t, write, buffer, lenp, ppos);
2474 	if (err < 0)
2475 		return err;
2476 
2477 	if (write) {
2478 		/*
2479 		 * Poor man's atomic or. Not worth adding a primitive
2480 		 * to everyone's atomic.h for this
2481 		 */
2482 		int i;
2483 		for (i = 0; i < BITS_PER_LONG && tmptaint >> i; i++) {
2484 			if ((tmptaint >> i) & 1)
2485 				add_taint(i, LOCKDEP_STILL_OK);
2486 		}
2487 	}
2488 
2489 	return err;
2490 }
2491 
2492 #ifdef CONFIG_PRINTK
2493 static int proc_dointvec_minmax_sysadmin(struct ctl_table *table, int write,
2494 				void __user *buffer, size_t *lenp, loff_t *ppos)
2495 {
2496 	if (write && !capable(CAP_SYS_ADMIN))
2497 		return -EPERM;
2498 
2499 	return proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2500 }
2501 #endif
2502 
2503 struct do_proc_dointvec_minmax_conv_param {
2504 	int *min;
2505 	int *max;
2506 };
2507 
2508 static int do_proc_dointvec_minmax_conv(bool *negp, unsigned long *lvalp,
2509 					int *valp,
2510 					int write, void *data)
2511 {
2512 	struct do_proc_dointvec_minmax_conv_param *param = data;
2513 	if (write) {
2514 		int val = *negp ? -*lvalp : *lvalp;
2515 		if ((param->min && *param->min > val) ||
2516 		    (param->max && *param->max < val))
2517 			return -EINVAL;
2518 		*valp = val;
2519 	} else {
2520 		int val = *valp;
2521 		if (val < 0) {
2522 			*negp = true;
2523 			*lvalp = -(unsigned long)val;
2524 		} else {
2525 			*negp = false;
2526 			*lvalp = (unsigned long)val;
2527 		}
2528 	}
2529 	return 0;
2530 }
2531 
2532 /**
2533  * proc_dointvec_minmax - read a vector of integers with min/max values
2534  * @table: the sysctl table
2535  * @write: %TRUE if this is a write to the sysctl file
2536  * @buffer: the user buffer
2537  * @lenp: the size of the user buffer
2538  * @ppos: file position
2539  *
2540  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2541  * values from/to the user buffer, treated as an ASCII string.
2542  *
2543  * This routine will ensure the values are within the range specified by
2544  * table->extra1 (min) and table->extra2 (max).
2545  *
2546  * Returns 0 on success.
2547  */
2548 int proc_dointvec_minmax(struct ctl_table *table, int write,
2549 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2550 {
2551 	struct do_proc_dointvec_minmax_conv_param param = {
2552 		.min = (int *) table->extra1,
2553 		.max = (int *) table->extra2,
2554 	};
2555 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2556 				do_proc_dointvec_minmax_conv, &param);
2557 }
2558 
2559 struct do_proc_douintvec_minmax_conv_param {
2560 	unsigned int *min;
2561 	unsigned int *max;
2562 };
2563 
2564 static int do_proc_douintvec_minmax_conv(unsigned long *lvalp,
2565 					 unsigned int *valp,
2566 					 int write, void *data)
2567 {
2568 	struct do_proc_douintvec_minmax_conv_param *param = data;
2569 
2570 	if (write) {
2571 		unsigned int val = *lvalp;
2572 
2573 		if (*lvalp > UINT_MAX)
2574 			return -EINVAL;
2575 
2576 		if ((param->min && *param->min > val) ||
2577 		    (param->max && *param->max < val))
2578 			return -ERANGE;
2579 
2580 		*valp = val;
2581 	} else {
2582 		unsigned int val = *valp;
2583 		*lvalp = (unsigned long) val;
2584 	}
2585 
2586 	return 0;
2587 }
2588 
2589 /**
2590  * proc_douintvec_minmax - read a vector of unsigned ints with min/max values
2591  * @table: the sysctl table
2592  * @write: %TRUE if this is a write to the sysctl file
2593  * @buffer: the user buffer
2594  * @lenp: the size of the user buffer
2595  * @ppos: file position
2596  *
2597  * Reads/writes up to table->maxlen/sizeof(unsigned int) unsigned integer
2598  * values from/to the user buffer, treated as an ASCII string. Negative
2599  * strings are not allowed.
2600  *
2601  * This routine will ensure the values are within the range specified by
2602  * table->extra1 (min) and table->extra2 (max). There is a final sanity
2603  * check for UINT_MAX to avoid having to support wrap around uses from
2604  * userspace.
2605  *
2606  * Returns 0 on success.
2607  */
2608 int proc_douintvec_minmax(struct ctl_table *table, int write,
2609 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2610 {
2611 	struct do_proc_douintvec_minmax_conv_param param = {
2612 		.min = (unsigned int *) table->extra1,
2613 		.max = (unsigned int *) table->extra2,
2614 	};
2615 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2616 				 do_proc_douintvec_minmax_conv, &param);
2617 }
2618 
2619 static int do_proc_dopipe_max_size_conv(unsigned long *lvalp,
2620 					unsigned int *valp,
2621 					int write, void *data)
2622 {
2623 	if (write) {
2624 		unsigned int val;
2625 
2626 		val = round_pipe_size(*lvalp);
2627 		if (val == 0)
2628 			return -EINVAL;
2629 
2630 		*valp = val;
2631 	} else {
2632 		unsigned int val = *valp;
2633 		*lvalp = (unsigned long) val;
2634 	}
2635 
2636 	return 0;
2637 }
2638 
2639 static int proc_dopipe_max_size(struct ctl_table *table, int write,
2640 				void __user *buffer, size_t *lenp, loff_t *ppos)
2641 {
2642 	return do_proc_douintvec(table, write, buffer, lenp, ppos,
2643 				 do_proc_dopipe_max_size_conv, NULL);
2644 }
2645 
2646 static void validate_coredump_safety(void)
2647 {
2648 #ifdef CONFIG_COREDUMP
2649 	if (suid_dumpable == SUID_DUMP_ROOT &&
2650 	    core_pattern[0] != '/' && core_pattern[0] != '|') {
2651 		printk(KERN_WARNING
2652 "Unsafe core_pattern used with fs.suid_dumpable=2.\n"
2653 "Pipe handler or fully qualified core dump path required.\n"
2654 "Set kernel.core_pattern before fs.suid_dumpable.\n"
2655 		);
2656 	}
2657 #endif
2658 }
2659 
2660 static int proc_dointvec_minmax_coredump(struct ctl_table *table, int write,
2661 		void __user *buffer, size_t *lenp, loff_t *ppos)
2662 {
2663 	int error = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
2664 	if (!error)
2665 		validate_coredump_safety();
2666 	return error;
2667 }
2668 
2669 #ifdef CONFIG_COREDUMP
2670 static int proc_dostring_coredump(struct ctl_table *table, int write,
2671 		  void __user *buffer, size_t *lenp, loff_t *ppos)
2672 {
2673 	int error = proc_dostring(table, write, buffer, lenp, ppos);
2674 	if (!error)
2675 		validate_coredump_safety();
2676 	return error;
2677 }
2678 #endif
2679 
2680 static int __do_proc_doulongvec_minmax(void *data, struct ctl_table *table, int write,
2681 				     void __user *buffer,
2682 				     size_t *lenp, loff_t *ppos,
2683 				     unsigned long convmul,
2684 				     unsigned long convdiv)
2685 {
2686 	unsigned long *i, *min, *max;
2687 	int vleft, first = 1, err = 0;
2688 	size_t left;
2689 	char *kbuf = NULL, *p;
2690 
2691 	if (!data || !table->maxlen || !*lenp || (*ppos && !write)) {
2692 		*lenp = 0;
2693 		return 0;
2694 	}
2695 
2696 	i = (unsigned long *) data;
2697 	min = (unsigned long *) table->extra1;
2698 	max = (unsigned long *) table->extra2;
2699 	vleft = table->maxlen / sizeof(unsigned long);
2700 	left = *lenp;
2701 
2702 	if (write) {
2703 		if (proc_first_pos_non_zero_ignore(ppos, table))
2704 			goto out;
2705 
2706 		if (left > PAGE_SIZE - 1)
2707 			left = PAGE_SIZE - 1;
2708 		p = kbuf = memdup_user_nul(buffer, left);
2709 		if (IS_ERR(kbuf))
2710 			return PTR_ERR(kbuf);
2711 	}
2712 
2713 	for (; left && vleft--; i++, first = 0) {
2714 		unsigned long val;
2715 
2716 		if (write) {
2717 			bool neg;
2718 
2719 			left -= proc_skip_spaces(&p);
2720 
2721 			err = proc_get_long(&p, &left, &val, &neg,
2722 					     proc_wspace_sep,
2723 					     sizeof(proc_wspace_sep), NULL);
2724 			if (err)
2725 				break;
2726 			if (neg)
2727 				continue;
2728 			val = convmul * val / convdiv;
2729 			if ((min && val < *min) || (max && val > *max))
2730 				continue;
2731 			*i = val;
2732 		} else {
2733 			val = convdiv * (*i) / convmul;
2734 			if (!first) {
2735 				err = proc_put_char(&buffer, &left, '\t');
2736 				if (err)
2737 					break;
2738 			}
2739 			err = proc_put_long(&buffer, &left, val, false);
2740 			if (err)
2741 				break;
2742 		}
2743 	}
2744 
2745 	if (!write && !first && left && !err)
2746 		err = proc_put_char(&buffer, &left, '\n');
2747 	if (write && !err)
2748 		left -= proc_skip_spaces(&p);
2749 	if (write) {
2750 		kfree(kbuf);
2751 		if (first)
2752 			return err ? : -EINVAL;
2753 	}
2754 	*lenp -= left;
2755 out:
2756 	*ppos += *lenp;
2757 	return err;
2758 }
2759 
2760 static int do_proc_doulongvec_minmax(struct ctl_table *table, int write,
2761 				     void __user *buffer,
2762 				     size_t *lenp, loff_t *ppos,
2763 				     unsigned long convmul,
2764 				     unsigned long convdiv)
2765 {
2766 	return __do_proc_doulongvec_minmax(table->data, table, write,
2767 			buffer, lenp, ppos, convmul, convdiv);
2768 }
2769 
2770 /**
2771  * proc_doulongvec_minmax - read a vector of long integers with min/max values
2772  * @table: the sysctl table
2773  * @write: %TRUE if this is a write to the sysctl file
2774  * @buffer: the user buffer
2775  * @lenp: the size of the user buffer
2776  * @ppos: file position
2777  *
2778  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2779  * values from/to the user buffer, treated as an ASCII string.
2780  *
2781  * This routine will ensure the values are within the range specified by
2782  * table->extra1 (min) and table->extra2 (max).
2783  *
2784  * Returns 0 on success.
2785  */
2786 int proc_doulongvec_minmax(struct ctl_table *table, int write,
2787 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2788 {
2789     return do_proc_doulongvec_minmax(table, write, buffer, lenp, ppos, 1l, 1l);
2790 }
2791 
2792 /**
2793  * proc_doulongvec_ms_jiffies_minmax - read a vector of millisecond values with min/max values
2794  * @table: the sysctl table
2795  * @write: %TRUE if this is a write to the sysctl file
2796  * @buffer: the user buffer
2797  * @lenp: the size of the user buffer
2798  * @ppos: file position
2799  *
2800  * Reads/writes up to table->maxlen/sizeof(unsigned long) unsigned long
2801  * values from/to the user buffer, treated as an ASCII string. The values
2802  * are treated as milliseconds, and converted to jiffies when they are stored.
2803  *
2804  * This routine will ensure the values are within the range specified by
2805  * table->extra1 (min) and table->extra2 (max).
2806  *
2807  * Returns 0 on success.
2808  */
2809 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
2810 				      void __user *buffer,
2811 				      size_t *lenp, loff_t *ppos)
2812 {
2813     return do_proc_doulongvec_minmax(table, write, buffer,
2814 				     lenp, ppos, HZ, 1000l);
2815 }
2816 
2817 
2818 static int do_proc_dointvec_jiffies_conv(bool *negp, unsigned long *lvalp,
2819 					 int *valp,
2820 					 int write, void *data)
2821 {
2822 	if (write) {
2823 		if (*lvalp > INT_MAX / HZ)
2824 			return 1;
2825 		*valp = *negp ? -(*lvalp*HZ) : (*lvalp*HZ);
2826 	} else {
2827 		int val = *valp;
2828 		unsigned long lval;
2829 		if (val < 0) {
2830 			*negp = true;
2831 			lval = -(unsigned long)val;
2832 		} else {
2833 			*negp = false;
2834 			lval = (unsigned long)val;
2835 		}
2836 		*lvalp = lval / HZ;
2837 	}
2838 	return 0;
2839 }
2840 
2841 static int do_proc_dointvec_userhz_jiffies_conv(bool *negp, unsigned long *lvalp,
2842 						int *valp,
2843 						int write, void *data)
2844 {
2845 	if (write) {
2846 		if (USER_HZ < HZ && *lvalp > (LONG_MAX / HZ) * USER_HZ)
2847 			return 1;
2848 		*valp = clock_t_to_jiffies(*negp ? -*lvalp : *lvalp);
2849 	} else {
2850 		int val = *valp;
2851 		unsigned long lval;
2852 		if (val < 0) {
2853 			*negp = true;
2854 			lval = -(unsigned long)val;
2855 		} else {
2856 			*negp = false;
2857 			lval = (unsigned long)val;
2858 		}
2859 		*lvalp = jiffies_to_clock_t(lval);
2860 	}
2861 	return 0;
2862 }
2863 
2864 static int do_proc_dointvec_ms_jiffies_conv(bool *negp, unsigned long *lvalp,
2865 					    int *valp,
2866 					    int write, void *data)
2867 {
2868 	if (write) {
2869 		unsigned long jif = msecs_to_jiffies(*negp ? -*lvalp : *lvalp);
2870 
2871 		if (jif > INT_MAX)
2872 			return 1;
2873 		*valp = (int)jif;
2874 	} else {
2875 		int val = *valp;
2876 		unsigned long lval;
2877 		if (val < 0) {
2878 			*negp = true;
2879 			lval = -(unsigned long)val;
2880 		} else {
2881 			*negp = false;
2882 			lval = (unsigned long)val;
2883 		}
2884 		*lvalp = jiffies_to_msecs(lval);
2885 	}
2886 	return 0;
2887 }
2888 
2889 /**
2890  * proc_dointvec_jiffies - read a vector of integers as seconds
2891  * @table: the sysctl table
2892  * @write: %TRUE if this is a write to the sysctl file
2893  * @buffer: the user buffer
2894  * @lenp: the size of the user buffer
2895  * @ppos: file position
2896  *
2897  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2898  * values from/to the user buffer, treated as an ASCII string.
2899  * The values read are assumed to be in seconds, and are converted into
2900  * jiffies.
2901  *
2902  * Returns 0 on success.
2903  */
2904 int proc_dointvec_jiffies(struct ctl_table *table, int write,
2905 			  void __user *buffer, size_t *lenp, loff_t *ppos)
2906 {
2907     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2908 		    	    do_proc_dointvec_jiffies_conv,NULL);
2909 }
2910 
2911 /**
2912  * proc_dointvec_userhz_jiffies - read a vector of integers as 1/USER_HZ seconds
2913  * @table: the sysctl table
2914  * @write: %TRUE if this is a write to the sysctl file
2915  * @buffer: the user buffer
2916  * @lenp: the size of the user buffer
2917  * @ppos: pointer to the file position
2918  *
2919  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2920  * values from/to the user buffer, treated as an ASCII string.
2921  * The values read are assumed to be in 1/USER_HZ seconds, and
2922  * are converted into jiffies.
2923  *
2924  * Returns 0 on success.
2925  */
2926 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
2927 				 void __user *buffer, size_t *lenp, loff_t *ppos)
2928 {
2929     return do_proc_dointvec(table,write,buffer,lenp,ppos,
2930 		    	    do_proc_dointvec_userhz_jiffies_conv,NULL);
2931 }
2932 
2933 /**
2934  * proc_dointvec_ms_jiffies - read a vector of integers as 1 milliseconds
2935  * @table: the sysctl table
2936  * @write: %TRUE if this is a write to the sysctl file
2937  * @buffer: the user buffer
2938  * @lenp: the size of the user buffer
2939  * @ppos: file position
2940  * @ppos: the current position in the file
2941  *
2942  * Reads/writes up to table->maxlen/sizeof(unsigned int) integer
2943  * values from/to the user buffer, treated as an ASCII string.
2944  * The values read are assumed to be in 1/1000 seconds, and
2945  * are converted into jiffies.
2946  *
2947  * Returns 0 on success.
2948  */
2949 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
2950 			     void __user *buffer, size_t *lenp, loff_t *ppos)
2951 {
2952 	return do_proc_dointvec(table, write, buffer, lenp, ppos,
2953 				do_proc_dointvec_ms_jiffies_conv, NULL);
2954 }
2955 
2956 static int proc_do_cad_pid(struct ctl_table *table, int write,
2957 			   void __user *buffer, size_t *lenp, loff_t *ppos)
2958 {
2959 	struct pid *new_pid;
2960 	pid_t tmp;
2961 	int r;
2962 
2963 	tmp = pid_vnr(cad_pid);
2964 
2965 	r = __do_proc_dointvec(&tmp, table, write, buffer,
2966 			       lenp, ppos, NULL, NULL);
2967 	if (r || !write)
2968 		return r;
2969 
2970 	new_pid = find_get_pid(tmp);
2971 	if (!new_pid)
2972 		return -ESRCH;
2973 
2974 	put_pid(xchg(&cad_pid, new_pid));
2975 	return 0;
2976 }
2977 
2978 /**
2979  * proc_do_large_bitmap - read/write from/to a large bitmap
2980  * @table: the sysctl table
2981  * @write: %TRUE if this is a write to the sysctl file
2982  * @buffer: the user buffer
2983  * @lenp: the size of the user buffer
2984  * @ppos: file position
2985  *
2986  * The bitmap is stored at table->data and the bitmap length (in bits)
2987  * in table->maxlen.
2988  *
2989  * We use a range comma separated format (e.g. 1,3-4,10-10) so that
2990  * large bitmaps may be represented in a compact manner. Writing into
2991  * the file will clear the bitmap then update it with the given input.
2992  *
2993  * Returns 0 on success.
2994  */
2995 int proc_do_large_bitmap(struct ctl_table *table, int write,
2996 			 void __user *buffer, size_t *lenp, loff_t *ppos)
2997 {
2998 	int err = 0;
2999 	bool first = 1;
3000 	size_t left = *lenp;
3001 	unsigned long bitmap_len = table->maxlen;
3002 	unsigned long *bitmap = *(unsigned long **) table->data;
3003 	unsigned long *tmp_bitmap = NULL;
3004 	char tr_a[] = { '-', ',', '\n' }, tr_b[] = { ',', '\n', 0 }, c;
3005 
3006 	if (!bitmap || !bitmap_len || !left || (*ppos && !write)) {
3007 		*lenp = 0;
3008 		return 0;
3009 	}
3010 
3011 	if (write) {
3012 		char *kbuf, *p;
3013 
3014 		if (left > PAGE_SIZE - 1)
3015 			left = PAGE_SIZE - 1;
3016 
3017 		p = kbuf = memdup_user_nul(buffer, left);
3018 		if (IS_ERR(kbuf))
3019 			return PTR_ERR(kbuf);
3020 
3021 		tmp_bitmap = kzalloc(BITS_TO_LONGS(bitmap_len) * sizeof(unsigned long),
3022 				     GFP_KERNEL);
3023 		if (!tmp_bitmap) {
3024 			kfree(kbuf);
3025 			return -ENOMEM;
3026 		}
3027 		proc_skip_char(&p, &left, '\n');
3028 		while (!err && left) {
3029 			unsigned long val_a, val_b;
3030 			bool neg;
3031 
3032 			err = proc_get_long(&p, &left, &val_a, &neg, tr_a,
3033 					     sizeof(tr_a), &c);
3034 			if (err)
3035 				break;
3036 			if (val_a >= bitmap_len || neg) {
3037 				err = -EINVAL;
3038 				break;
3039 			}
3040 
3041 			val_b = val_a;
3042 			if (left) {
3043 				p++;
3044 				left--;
3045 			}
3046 
3047 			if (c == '-') {
3048 				err = proc_get_long(&p, &left, &val_b,
3049 						     &neg, tr_b, sizeof(tr_b),
3050 						     &c);
3051 				if (err)
3052 					break;
3053 				if (val_b >= bitmap_len || neg ||
3054 				    val_a > val_b) {
3055 					err = -EINVAL;
3056 					break;
3057 				}
3058 				if (left) {
3059 					p++;
3060 					left--;
3061 				}
3062 			}
3063 
3064 			bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
3065 			first = 0;
3066 			proc_skip_char(&p, &left, '\n');
3067 		}
3068 		kfree(kbuf);
3069 	} else {
3070 		unsigned long bit_a, bit_b = 0;
3071 
3072 		while (left) {
3073 			bit_a = find_next_bit(bitmap, bitmap_len, bit_b);
3074 			if (bit_a >= bitmap_len)
3075 				break;
3076 			bit_b = find_next_zero_bit(bitmap, bitmap_len,
3077 						   bit_a + 1) - 1;
3078 
3079 			if (!first) {
3080 				err = proc_put_char(&buffer, &left, ',');
3081 				if (err)
3082 					break;
3083 			}
3084 			err = proc_put_long(&buffer, &left, bit_a, false);
3085 			if (err)
3086 				break;
3087 			if (bit_a != bit_b) {
3088 				err = proc_put_char(&buffer, &left, '-');
3089 				if (err)
3090 					break;
3091 				err = proc_put_long(&buffer, &left, bit_b, false);
3092 				if (err)
3093 					break;
3094 			}
3095 
3096 			first = 0; bit_b++;
3097 		}
3098 		if (!err)
3099 			err = proc_put_char(&buffer, &left, '\n');
3100 	}
3101 
3102 	if (!err) {
3103 		if (write) {
3104 			if (*ppos)
3105 				bitmap_or(bitmap, bitmap, tmp_bitmap, bitmap_len);
3106 			else
3107 				bitmap_copy(bitmap, tmp_bitmap, bitmap_len);
3108 		}
3109 		*lenp -= left;
3110 		*ppos += *lenp;
3111 	}
3112 
3113 	kfree(tmp_bitmap);
3114 	return err;
3115 }
3116 
3117 #else /* CONFIG_PROC_SYSCTL */
3118 
3119 int proc_dostring(struct ctl_table *table, int write,
3120 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3121 {
3122 	return -ENOSYS;
3123 }
3124 
3125 int proc_dointvec(struct ctl_table *table, int write,
3126 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3127 {
3128 	return -ENOSYS;
3129 }
3130 
3131 int proc_douintvec(struct ctl_table *table, int write,
3132 		  void __user *buffer, size_t *lenp, loff_t *ppos)
3133 {
3134 	return -ENOSYS;
3135 }
3136 
3137 int proc_dointvec_minmax(struct ctl_table *table, int write,
3138 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3139 {
3140 	return -ENOSYS;
3141 }
3142 
3143 int proc_douintvec_minmax(struct ctl_table *table, int write,
3144 			  void __user *buffer, size_t *lenp, loff_t *ppos)
3145 {
3146 	return -ENOSYS;
3147 }
3148 
3149 int proc_dointvec_jiffies(struct ctl_table *table, int write,
3150 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3151 {
3152 	return -ENOSYS;
3153 }
3154 
3155 int proc_dointvec_userhz_jiffies(struct ctl_table *table, int write,
3156 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3157 {
3158 	return -ENOSYS;
3159 }
3160 
3161 int proc_dointvec_ms_jiffies(struct ctl_table *table, int write,
3162 			     void __user *buffer, size_t *lenp, loff_t *ppos)
3163 {
3164 	return -ENOSYS;
3165 }
3166 
3167 int proc_doulongvec_minmax(struct ctl_table *table, int write,
3168 		    void __user *buffer, size_t *lenp, loff_t *ppos)
3169 {
3170 	return -ENOSYS;
3171 }
3172 
3173 int proc_doulongvec_ms_jiffies_minmax(struct ctl_table *table, int write,
3174 				      void __user *buffer,
3175 				      size_t *lenp, loff_t *ppos)
3176 {
3177     return -ENOSYS;
3178 }
3179 
3180 
3181 #endif /* CONFIG_PROC_SYSCTL */
3182 
3183 /*
3184  * No sense putting this after each symbol definition, twice,
3185  * exception granted :-)
3186  */
3187 EXPORT_SYMBOL(proc_dointvec);
3188 EXPORT_SYMBOL(proc_douintvec);
3189 EXPORT_SYMBOL(proc_dointvec_jiffies);
3190 EXPORT_SYMBOL(proc_dointvec_minmax);
3191 EXPORT_SYMBOL_GPL(proc_douintvec_minmax);
3192 EXPORT_SYMBOL(proc_dointvec_userhz_jiffies);
3193 EXPORT_SYMBOL(proc_dointvec_ms_jiffies);
3194 EXPORT_SYMBOL(proc_dostring);
3195 EXPORT_SYMBOL(proc_doulongvec_minmax);
3196 EXPORT_SYMBOL(proc_doulongvec_ms_jiffies_minmax);
3197